feat(adminui): F15.2 batch 2 — topology entity CRUD

Same single-page edit-or-create pattern as batch 1, applied to the
foundational topology entities. After this batch the whole hierarchy
(cluster → nodes → UNS areas → UNS lines → namespaces → drivers) is
fully editable through the UI.

- ClusterEdit.razor                  /clusters/{id}/edit
  Update + delete for an existing cluster. NodeCount stays coupled to
  RedundancyMode (None→1, Warm/Hot→2). ModifiedBy taken from
  AuthenticationStateProvider.
- NodeEdit.razor                     /clusters/{id}/nodes/{new|nodeId}
  Full ClusterNode CRUD. ApplicationUri uniqueness is enforced by EF
  index; ServiceLevelBase defaults to 200 (primary preference) on
  create; per-node DriverConfigOverridesJson validated as JSON.
- UnsAreaEdit.razor                  /clusters/{id}/uns/areas/{new|id}
- UnsLineEdit.razor                  /clusters/{id}/uns/lines/{new|id}
  UNS structure CRUD; Lines pick their parent Area from a select that
  loads the cluster's areas.

List pages updated:
- ClusterOverview now shows an "Edit cluster" button + a "New node"
  action on the nodes panel + per-row Edit buttons.
- ClusterUns gains New/Edit affordances for both Areas and Lines.

All 9 integration tests still green; no regressions.

src/Server/ZB.MOM.WW.OtOpcUa.AdminUI/Components/Pages/Clusters/ClusterEdit.razor

@@ -0,0 +1,200 @@
+@page "/clusters/{ClusterId}/edit"
+@* Edit page for an existing ServerCluster. The /clusters/new route lives in NewCluster.razor;
+   this page handles only the update case so the form can disable ClusterId (immutable). *@
+@attribute [Microsoft.AspNetCore.Authorization.Authorize]
+@rendermode RenderMode.InteractiveServer
+@using Microsoft.AspNetCore.Components.Forms
+@using Microsoft.EntityFrameworkCore
+@using System.ComponentModel.DataAnnotations
+@using ZB.MOM.WW.OtOpcUa.Configuration
+@using ZB.MOM.WW.OtOpcUa.Configuration.Entities
+@using ZB.MOM.WW.OtOpcUa.Configuration.Enums
+@inject IDbContextFactory<OtOpcUaConfigDbContext> DbFactory
+@inject NavigationManager Nav
+@inject AuthenticationStateProvider AuthState
+
+<div class="d-flex justify-content-between align-items-center mb-3">
+    <h4 class="mb-0">Edit cluster &middot; <span class="mono">@ClusterId</span></h4>
+    <a href="/clusters/@ClusterId" class="btn btn-outline-secondary btn-sm">Cancel</a>
+</div>
+
+<ClusterNav ClusterId="@ClusterId" ActiveTab="overview" />
+
+@if (!_loaded)
+{
+    <p>Loading…</p>
+}
+else if (_existing is null)
+{
+    <section class="panel notice rise" style="animation-delay:.02s">
+        Cluster <span class="mono">@ClusterId</span> was not found.
+    </section>
+}
+else
+{
+    <EditForm Model="_form" OnValidSubmit="SubmitAsync" FormName="clusterEdit">
+        <DataAnnotationsValidator />
+        <section class="panel rise" style="animation-delay:.02s">
+            <div class="panel-head">Identity</div>
+            <div style="padding:1rem">
+                <div class="mb-3">
+                    <label class="form-label">ClusterId</label>
+                    <input class="form-control form-control-sm mono" value="@ClusterId" disabled />
+                    <div class="form-text">Immutable after creation. Operator-visible everywhere; renames would invalidate every downstream reference.</div>
+                </div>
+                <div class="mb-3">
+                    <label class="form-label" for="name">Name</label>
+                    <InputText id="name" @bind-Value="_form.Name" class="form-control form-control-sm" />
+                </div>
+                <div class="row">
+                    <div class="col-md-6 mb-3">
+                        <label class="form-label" for="enterprise">Enterprise</label>
+                        <InputText id="enterprise" @bind-Value="_form.Enterprise" class="form-control form-control-sm" />
+                    </div>
+                    <div class="col-md-6 mb-3">
+                        <label class="form-label" for="site">Site</label>
+                        <InputText id="site" @bind-Value="_form.Site" class="form-control form-control-sm" />
+                    </div>
+                </div>
+                <div class="mb-3">
+                    <label class="form-label">Enabled</label>
+                    <div class="form-check form-switch">
+                        <InputCheckbox @bind-Value="_form.Enabled" class="form-check-input" />
+                        <label class="form-check-label">Spawn drivers + serve endpoints in deployments</label>
+                    </div>
+                </div>
+            </div>
+        </section>
+
+        <section class="panel rise mt-3" style="animation-delay:.08s">
+            <div class="panel-head">Topology</div>
+            <div style="padding:1rem">
+                <div class="mb-3">
+                    <label class="form-label" for="redundancy">Redundancy mode</label>
+                    <InputSelect id="redundancy" @bind-Value="_form.RedundancyMode" class="form-select form-select-sm">
+                        <option value="@RedundancyMode.None">None (1 node)</option>
+                        <option value="@RedundancyMode.Warm">Warm (2 nodes)</option>
+                        <option value="@RedundancyMode.Hot">Hot (2 nodes)</option>
+                    </InputSelect>
+                </div>
+                <div class="mb-3">
+                    <label class="form-label" for="notes">Notes</label>
+                    <InputTextArea id="notes" @bind-Value="_form.Notes" class="form-control form-control-sm" rows="3" />
+                </div>
+            </div>
+        </section>
+
+        @if (!string.IsNullOrWhiteSpace(_error))
+        {
+            <div class="panel notice mt-3" style="border-color:var(--alert)">@_error</div>
+        }
+
+        <div class="mt-3 d-flex gap-2">
+            <button type="submit" class="btn btn-primary" disabled="@_busy">
+                @if (_busy) { <span class="spinner-border spinner-border-sm me-1"></span> }
+                Save changes
+            </button>
+            <a href="/clusters/@ClusterId" class="btn btn-outline-secondary">Cancel</a>
+            <button type="button" class="btn btn-outline-danger ms-auto" @onclick="DeleteAsync" disabled="@_busy">
+                Delete cluster
+            </button>
+        </div>
+    </EditForm>
+}
+
+@code {
+    [Parameter] public string ClusterId { get; set; } = "";
+
+    private FormModel _form = new();
+    private ServerCluster? _existing;
+    private bool _loaded;
+    private bool _busy;
+    private string? _error;
+
+    protected override async Task OnInitializedAsync()
+    {
+        await using var db = await DbFactory.CreateDbContextAsync();
+        _existing = await db.ServerClusters.AsNoTracking()
+            .FirstOrDefaultAsync(c => c.ClusterId == ClusterId);
+        if (_existing is not null)
+        {
+            _form = new FormModel
+            {
+                Name = _existing.Name,
+                Enterprise = _existing.Enterprise,
+                Site = _existing.Site,
+                RedundancyMode = _existing.RedundancyMode,
+                Enabled = _existing.Enabled,
+                Notes = _existing.Notes,
+            };
+        }
+        _loaded = true;
+    }
+
+    private async Task SubmitAsync()
+    {
+        _busy = true;
+        _error = null;
+        try
+        {
+            await using var db = await DbFactory.CreateDbContextAsync();
+            var entity = await db.ServerClusters.FirstOrDefaultAsync(c => c.ClusterId == ClusterId);
+            if (entity is null) { _error = "Cluster no longer exists."; return; }
+
+            var auth = await AuthState.GetAuthenticationStateAsync();
+            entity.Name = _form.Name;
+            entity.Enterprise = _form.Enterprise;
+            entity.Site = _form.Site;
+            entity.RedundancyMode = _form.RedundancyMode;
+            entity.NodeCount = _form.RedundancyMode == RedundancyMode.None ? (byte)1 : (byte)2;
+            entity.Enabled = _form.Enabled;
+            entity.Notes = string.IsNullOrWhiteSpace(_form.Notes) ? null : _form.Notes;
+            entity.ModifiedAt = DateTime.UtcNow;
+            entity.ModifiedBy = auth.User.Identity?.Name ?? "(anonymous)";
+
+            await db.SaveChangesAsync();
+            Nav.NavigateTo($"/clusters/{ClusterId}");
+        }
+        catch (Exception ex)
+        {
+            _error = ex.Message;
+        }
+        finally
+        {
+            _busy = false;
+        }
+    }
+
+    private async Task DeleteAsync()
+    {
+        _busy = true;
+        _error = null;
+        try
+        {
+            await using var db = await DbFactory.CreateDbContextAsync();
+            var entity = await db.ServerClusters.FirstOrDefaultAsync(c => c.ClusterId == ClusterId);
+            if (entity is null) { Nav.NavigateTo("/clusters"); return; }
+            db.ServerClusters.Remove(entity);
+            await db.SaveChangesAsync();
+            Nav.NavigateTo("/clusters");
+        }
+        catch (Exception ex)
+        {
+            _error = $"Delete failed: {ex.Message}. Likely because nodes, namespaces, drivers, or other rows still reference this cluster — remove them first.";
+        }
+        finally
+        {
+            _busy = false;
+        }
+    }
+
+    private sealed class FormModel
+    {
+        [Required] public string Name { get; set; } = "";
+        [Required] public string Enterprise { get; set; } = "";
+        [Required] public string Site { get; set; } = "";
+        public RedundancyMode RedundancyMode { get; set; } = RedundancyMode.None;
+        public bool Enabled { get; set; } = true;
+        public string? Notes { get; set; }
+    }
+}

src/Server/ZB.MOM.WW.OtOpcUa.AdminUI/Components/Pages/Clusters/ClusterOverview.razor

@@ -26,7 +26,8 @@ else
             <span class="mono text-muted">@_cluster.ClusterId</span>
             @if (!_cluster.Enabled) { <span class="chip chip-idle ms-2">Disabled</span> }
         </div>
-        <div>
+        <div class="d-flex gap-2">
+            <a href="/clusters/@ClusterId/edit" class="btn btn-outline-secondary btn-sm">Edit cluster</a>
             <a href="/deployments" class="btn btn-outline-primary btn-sm">Deployments</a>
         </div>
     </div>
@@ -69,7 +70,10 @@ else
     </section>
 
     <section class="panel rise mt-3" style="animation-delay:.14s">
-        <div class="panel-head">Nodes</div>
+        <div class="panel-head d-flex align-items-center">
+            <span>Nodes</span>
+            <a href="/clusters/@ClusterId/nodes/new" class="btn btn-sm btn-outline-primary ms-auto">New node</a>
+        </div>
         @if (_nodes is null || _nodes.Count == 0)
         {
             <div style="padding:1rem" class="text-muted">No nodes registered.</div>
@@ -85,6 +89,7 @@ else
                             <th>OPC UA port</th>
                             <th>ApplicationUri</th>
                             <th class="num">ServiceLevel base</th>
+                            <th></th>
                         </tr>
                     </thead>
                     <tbody>
@@ -96,6 +101,7 @@ else
                                 <td class="num">@n.OpcUaPort</td>
                                 <td><span class="mono small">@n.ApplicationUri</span></td>
                                 <td class="num">@n.ServiceLevelBase</td>
+                                <td><a href="/clusters/@ClusterId/nodes/@n.NodeId" class="btn btn-sm btn-outline-primary">Edit</a></td>
                             </tr>
                         }
                     </tbody>

src/Server/ZB.MOM.WW.OtOpcUa.AdminUI/Components/Pages/Clusters/ClusterUns.razor

@@ -25,7 +25,10 @@ else
     </section>
 
     <section class="panel rise mt-3" style="animation-delay:.08s">
-        <div class="panel-head">Areas (level 3) &middot; @_areas.Count</div>
+        <div class="panel-head d-flex align-items-center">
+            <span>Areas (level 3) &middot; @_areas.Count</span>
+            <a href="/clusters/@ClusterId/uns/areas/new" class="btn btn-sm btn-outline-primary ms-auto">New area</a>
+        </div>
         @if (_areas.Count == 0)
         {
             <div style="padding:1rem" class="text-muted">No areas defined.</div>
@@ -34,7 +37,7 @@ else
         {
             <div class="table-wrap">
                 <table class="data-table">
-                    <thead><tr><th>UnsAreaId</th><th>Name</th><th>Notes</th></tr></thead>
+                    <thead><tr><th>UnsAreaId</th><th>Name</th><th>Notes</th><th></th></tr></thead>
                     <tbody>
                         @foreach (var a in _areas)
                         {
@@ -42,6 +45,7 @@ else
                                 <td><span class="mono">@a.UnsAreaId</span></td>
                                 <td>@a.Name</td>
                                 <td class="text-muted small">@(a.Notes ?? "")</td>
+                                <td><a href="/clusters/@ClusterId/uns/areas/@a.UnsAreaId" class="btn btn-sm btn-outline-primary">Edit</a></td>
                             </tr>
                         }
                     </tbody>
@@ -51,7 +55,10 @@ else
     </section>
 
     <section class="panel rise mt-3" style="animation-delay:.14s">
-        <div class="panel-head">Lines (level 4) &middot; @_lines.Count</div>
+        <div class="panel-head d-flex align-items-center">
+            <span>Lines (level 4) &middot; @_lines.Count</span>
+            <a href="/clusters/@ClusterId/uns/lines/new" class="btn btn-sm btn-outline-primary ms-auto">New line</a>
+        </div>
         @if (_lines.Count == 0)
         {
             <div style="padding:1rem" class="text-muted">No lines defined.</div>
@@ -60,7 +67,7 @@ else
         {
             <div class="table-wrap">
                 <table class="data-table">
-                    <thead><tr><th>UnsLineId</th><th>Name</th><th>Area</th><th>Notes</th></tr></thead>
+                    <thead><tr><th>UnsLineId</th><th>Name</th><th>Area</th><th>Notes</th><th></th></tr></thead>
                     <tbody>
                         @foreach (var l in _lines)
                         {
@@ -69,6 +76,7 @@ else
                                 <td>@l.Name</td>
                                 <td><span class="mono">@l.UnsAreaId</span></td>
                                 <td class="text-muted small">@(l.Notes ?? "")</td>
+                                <td><a href="/clusters/@ClusterId/uns/lines/@l.UnsLineId" class="btn btn-sm btn-outline-primary">Edit</a></td>
                             </tr>
                         }
                     </tbody>

src/Server/ZB.MOM.WW.OtOpcUa.AdminUI/Components/Pages/Clusters/NodeEdit.razor

@@ -0,0 +1,268 @@
+@page "/clusters/{ClusterId}/nodes/new"
+@page "/clusters/{ClusterId}/nodes/{NodeId}"
+@* ClusterNode CRUD. ApplicationUri is fleet-wide unique — the EF unique index enforces this
+   at SaveChanges. ServiceLevelBase defaults: 200 primary, 150 secondary. *@
+@attribute [Microsoft.AspNetCore.Authorization.Authorize]
+@rendermode RenderMode.InteractiveServer
+@using Microsoft.AspNetCore.Components.Forms
+@using Microsoft.EntityFrameworkCore
+@using System.ComponentModel.DataAnnotations
+@using ZB.MOM.WW.OtOpcUa.Configuration
+@using ZB.MOM.WW.OtOpcUa.Configuration.Entities
+@inject IDbContextFactory<OtOpcUaConfigDbContext> DbFactory
+@inject NavigationManager Nav
+@inject AuthenticationStateProvider AuthState
+
+<div class="d-flex justify-content-between align-items-center mb-3">
+    <h4 class="mb-0">@(IsNew ? "New node" : "Edit node") &middot; <span class="mono">@ClusterId</span></h4>
+    <a href="/clusters/@ClusterId" class="btn btn-outline-secondary btn-sm">Cancel</a>
+</div>
+
+<ClusterNav ClusterId="@ClusterId" ActiveTab="overview" />
+
+@if (!_loaded)
+{
+    <p>Loading…</p>
+}
+else if (!IsNew && _existing is null)
+{
+    <section class="panel notice rise" style="animation-delay:.02s">
+        Node <span class="mono">@NodeId</span> was not found in cluster <span class="mono">@ClusterId</span>.
+    </section>
+}
+else
+{
+    <EditForm Model="_form" OnValidSubmit="SubmitAsync" FormName="nodeEdit">
+        <DataAnnotationsValidator />
+        <section class="panel rise" style="animation-delay:.02s">
+            <div class="panel-head">Identity</div>
+            <div style="padding:1rem">
+                <div class="mb-3">
+                    <label class="form-label" for="nodeId">NodeId</label>
+                    <InputText id="nodeId" @bind-Value="_form.NodeId" disabled="@(!IsNew)"
+                               class="form-control form-control-sm mono"
+                               placeholder="LINE3-OPCUA-A" />
+                </div>
+                <div class="row">
+                    <div class="col-md-6 mb-3">
+                        <label class="form-label" for="host">Host</label>
+                        <InputText id="host" @bind-Value="_form.Host" class="form-control form-control-sm mono"
+                                   placeholder="line3-opc-a.plant.local" />
+                    </div>
+                    <div class="col-md-3 mb-3">
+                        <label class="form-label" for="port">OPC UA port</label>
+                        <InputNumber id="port" @bind-Value="_form.OpcUaPort" class="form-control form-control-sm" />
+                    </div>
+                    <div class="col-md-3 mb-3">
+                        <label class="form-label" for="dashport">Dashboard port</label>
+                        <InputNumber id="dashport" @bind-Value="_form.DashboardPort" class="form-control form-control-sm" />
+                    </div>
+                </div>
+                <div class="mb-3">
+                    <label class="form-label" for="uri">ApplicationUri</label>
+                    <InputText id="uri" @bind-Value="_form.ApplicationUri" class="form-control form-control-sm mono"
+                               placeholder="urn:zb:warsaw-west:line3:opc-a" />
+                    <div class="form-text">Must be unique fleet-wide. Clients pin trust here — never silently rewrite based on Host.</div>
+                </div>
+            </div>
+        </section>
+
+        <section class="panel rise mt-3" style="animation-delay:.08s">
+            <div class="panel-head">Redundancy + behaviour</div>
+            <div style="padding:1rem">
+                <div class="row">
+                    <div class="col-md-4 mb-3">
+                        <label class="form-label" for="slbase">ServiceLevel base</label>
+                        <InputNumber id="slbase" @bind-Value="_form.ServiceLevelBase" class="form-control form-control-sm" />
+                        <div class="form-text">200 = primary preference, 150 = secondary preference. Live ServiceLevel adjusts down on faults.</div>
+                    </div>
+                    <div class="col-md-4 mb-3">
+                        <label class="form-label">Enabled</label>
+                        <div class="form-check form-switch">
+                            <InputCheckbox @bind-Value="_form.Enabled" class="form-check-input" />
+                            <label class="form-check-label">Join the Akka cluster + serve endpoints</label>
+                        </div>
+                    </div>
+                </div>
+                <div class="mb-3">
+                    <label class="form-label" for="overrides">Driver config overrides (JSON, optional)</label>
+                    <InputTextArea id="overrides" @bind-Value="_form.DriverConfigOverridesJson" rows="6"
+                                   class="form-control form-control-sm mono"
+                                   placeholder='{ "drv-modbus-line3-01": { "endpoint": "10.0.0.43:502" } }' />
+                    <div class="form-text">Per-node merge over cluster-level <span class="mono">DriverInstance.DriverConfig</span>. Minimal by design — heavy node-specific config is a smell.</div>
+                </div>
+            </div>
+        </section>
+
+        @if (!string.IsNullOrWhiteSpace(_error))
+        {
+            <div class="panel notice mt-3" style="border-color:var(--alert)">@_error</div>
+        }
+
+        <div class="mt-3 d-flex gap-2">
+            <button type="submit" class="btn btn-primary" disabled="@_busy">
+                @if (_busy) { <span class="spinner-border spinner-border-sm me-1"></span> }
+                @(IsNew ? "Create" : "Save changes")
+            </button>
+            <a href="/clusters/@ClusterId" class="btn btn-outline-secondary">Cancel</a>
+            @if (!IsNew)
+            {
+                <button type="button" class="btn btn-outline-danger ms-auto" @onclick="DeleteAsync" disabled="@_busy">
+                    Delete
+                </button>
+            }
+        </div>
+    </EditForm>
+}
+
+@code {
+    [Parameter] public string ClusterId { get; set; } = "";
+    [Parameter] public string? NodeId { get; set; }
+
+    private bool IsNew => string.IsNullOrEmpty(NodeId);
+
+    private FormModel _form = new();
+    private ClusterNode? _existing;
+    private bool _loaded;
+    private bool _busy;
+    private string? _error;
+
+    protected override async Task OnInitializedAsync()
+    {
+        if (IsNew)
+        {
+            _form = new FormModel
+            {
+                NodeId = "",
+                Host = "",
+                OpcUaPort = 4840,
+                DashboardPort = 8081,
+                ApplicationUri = "",
+                ServiceLevelBase = 200,
+                Enabled = true,
+            };
+        }
+        else
+        {
+            await using var db = await DbFactory.CreateDbContextAsync();
+            _existing = await db.ClusterNodes.AsNoTracking()
+                .FirstOrDefaultAsync(n => n.ClusterId == ClusterId && n.NodeId == NodeId);
+            if (_existing is not null)
+            {
+                _form = new FormModel
+                {
+                    NodeId = _existing.NodeId,
+                    Host = _existing.Host,
+                    OpcUaPort = _existing.OpcUaPort,
+                    DashboardPort = _existing.DashboardPort,
+                    ApplicationUri = _existing.ApplicationUri,
+                    ServiceLevelBase = _existing.ServiceLevelBase,
+                    Enabled = _existing.Enabled,
+                    DriverConfigOverridesJson = _existing.DriverConfigOverridesJson,
+                };
+            }
+        }
+        _loaded = true;
+    }
+
+    private async Task SubmitAsync()
+    {
+        _busy = true;
+        _error = null;
+        try
+        {
+            if (!string.IsNullOrWhiteSpace(_form.DriverConfigOverridesJson))
+            {
+                try { using var _ = System.Text.Json.JsonDocument.Parse(_form.DriverConfigOverridesJson); }
+                catch { _error = "DriverConfigOverridesJson is not valid JSON."; return; }
+            }
+
+            await using var db = await DbFactory.CreateDbContextAsync();
+            if (IsNew)
+            {
+                if (await db.ClusterNodes.AnyAsync(n => n.NodeId == _form.NodeId))
+                {
+                    _error = $"Node '{_form.NodeId}' already exists.";
+                    return;
+                }
+                var auth = await AuthState.GetAuthenticationStateAsync();
+                db.ClusterNodes.Add(new ClusterNode
+                {
+                    NodeId = _form.NodeId,
+                    ClusterId = ClusterId,
+                    Host = _form.Host,
+                    OpcUaPort = _form.OpcUaPort,
+                    DashboardPort = _form.DashboardPort,
+                    ApplicationUri = _form.ApplicationUri,
+                    ServiceLevelBase = _form.ServiceLevelBase,
+                    Enabled = _form.Enabled,
+                    DriverConfigOverridesJson = string.IsNullOrWhiteSpace(_form.DriverConfigOverridesJson) ? null : _form.DriverConfigOverridesJson,
+                    CreatedAt = DateTime.UtcNow,
+                    CreatedBy = auth.User.Identity?.Name ?? "(anonymous)",
+                });
+            }
+            else
+            {
+                var entity = await db.ClusterNodes.FirstOrDefaultAsync(
+                    n => n.ClusterId == ClusterId && n.NodeId == NodeId);
+                if (entity is null) { _error = "Row no longer exists."; return; }
+                entity.Host = _form.Host;
+                entity.OpcUaPort = _form.OpcUaPort;
+                entity.DashboardPort = _form.DashboardPort;
+                entity.ApplicationUri = _form.ApplicationUri;
+                entity.ServiceLevelBase = _form.ServiceLevelBase;
+                entity.Enabled = _form.Enabled;
+                entity.DriverConfigOverridesJson = string.IsNullOrWhiteSpace(_form.DriverConfigOverridesJson) ? null : _form.DriverConfigOverridesJson;
+            }
+            await db.SaveChangesAsync();
+            Nav.NavigateTo($"/clusters/{ClusterId}");
+        }
+        catch (Exception ex)
+        {
+            _error = ex.Message;
+        }
+        finally
+        {
+            _busy = false;
+        }
+    }
+
+    private async Task DeleteAsync()
+    {
+        if (IsNew) return;
+        _busy = true;
+        _error = null;
+        try
+        {
+            await using var db = await DbFactory.CreateDbContextAsync();
+            var entity = await db.ClusterNodes.FirstOrDefaultAsync(
+                n => n.ClusterId == ClusterId && n.NodeId == NodeId);
+            if (entity is null) { Nav.NavigateTo($"/clusters/{ClusterId}"); return; }
+            db.ClusterNodes.Remove(entity);
+            await db.SaveChangesAsync();
+            Nav.NavigateTo($"/clusters/{ClusterId}");
+        }
+        catch (Exception ex)
+        {
+            _error = ex.Message;
+        }
+        finally
+        {
+            _busy = false;
+        }
+    }
+
+    private sealed class FormModel
+    {
+        [Required, RegularExpression("^[A-Za-z0-9_-]+$")]
+        public string NodeId { get; set; } = "";
+        [Required] public string Host { get; set; } = "";
+        [Range(1, 65535)] public int OpcUaPort { get; set; } = 4840;
+        [Range(1, 65535)] public int DashboardPort { get; set; } = 8081;
+        [Required, RegularExpression("^urn:[A-Za-z0-9_:./-]+$")]
+        public string ApplicationUri { get; set; } = "";
+        [Range(0, 255)] public byte ServiceLevelBase { get; set; } = 200;
+        public bool Enabled { get; set; } = true;
+        public string? DriverConfigOverridesJson { get; set; }
+    }
+}

src/Server/ZB.MOM.WW.OtOpcUa.AdminUI/Components/Pages/Clusters/UnsAreaEdit.razor

@@ -0,0 +1,167 @@
+@page "/clusters/{ClusterId}/uns/areas/new"
+@page "/clusters/{ClusterId}/uns/areas/{UnsAreaId}"
+@attribute [Microsoft.AspNetCore.Authorization.Authorize]
+@rendermode RenderMode.InteractiveServer
+@using Microsoft.AspNetCore.Components.Forms
+@using Microsoft.EntityFrameworkCore
+@using System.ComponentModel.DataAnnotations
+@using ZB.MOM.WW.OtOpcUa.Configuration
+@using ZB.MOM.WW.OtOpcUa.Configuration.Entities
+@inject IDbContextFactory<OtOpcUaConfigDbContext> DbFactory
+@inject NavigationManager Nav
+
+<div class="d-flex justify-content-between align-items-center mb-3">
+    <h4 class="mb-0">@(IsNew ? "New UNS area" : "Edit UNS area") &middot; <span class="mono">@ClusterId</span></h4>
+    <a href="/clusters/@ClusterId/uns" class="btn btn-outline-secondary btn-sm">Cancel</a>
+</div>
+
+<ClusterNav ClusterId="@ClusterId" ActiveTab="uns" />
+
+@if (!_loaded)
+{
+    <p>Loading…</p>
+}
+else if (!IsNew && _existing is null)
+{
+    <section class="panel notice rise" style="animation-delay:.02s">
+        Area <span class="mono">@UnsAreaId</span> was not found.
+    </section>
+}
+else
+{
+    <EditForm Model="_form" OnValidSubmit="SubmitAsync" FormName="unsAreaEdit">
+        <DataAnnotationsValidator />
+        <section class="panel rise" style="animation-delay:.02s">
+            <div class="panel-head">UNS area (level 3)</div>
+            <div style="padding:1rem">
+                <div class="mb-3">
+                    <label class="form-label" for="aid">UnsAreaId</label>
+                    <InputText id="aid" @bind-Value="_form.UnsAreaId" disabled="@(!IsNew)"
+                               class="form-control form-control-sm mono" />
+                </div>
+                <div class="mb-3">
+                    <label class="form-label" for="name">Name</label>
+                    <InputText id="name" @bind-Value="_form.Name" class="form-control form-control-sm" />
+                </div>
+                <div class="mb-3">
+                    <label class="form-label" for="notes">Notes</label>
+                    <InputTextArea id="notes" @bind-Value="_form.Notes" class="form-control form-control-sm" rows="3" />
+                </div>
+            </div>
+        </section>
+
+        @if (!string.IsNullOrWhiteSpace(_error))
+        {
+            <div class="panel notice mt-3" style="border-color:var(--alert)">@_error</div>
+        }
+
+        <div class="mt-3 d-flex gap-2">
+            <button type="submit" class="btn btn-primary" disabled="@_busy">
+                @if (_busy) { <span class="spinner-border spinner-border-sm me-1"></span> }
+                @(IsNew ? "Create" : "Save changes")
+            </button>
+            <a href="/clusters/@ClusterId/uns" class="btn btn-outline-secondary">Cancel</a>
+            @if (!IsNew)
+            {
+                <button type="button" class="btn btn-outline-danger ms-auto" @onclick="DeleteAsync" disabled="@_busy">Delete</button>
+            }
+        </div>
+    </EditForm>
+}
+
+@code {
+    [Parameter] public string ClusterId { get; set; } = "";
+    [Parameter] public string? UnsAreaId { get; set; }
+
+    private bool IsNew => string.IsNullOrEmpty(UnsAreaId);
+
+    private FormModel _form = new();
+    private UnsArea? _existing;
+    private bool _loaded;
+    private bool _busy;
+    private string? _error;
+
+    protected override async Task OnInitializedAsync()
+    {
+        if (!IsNew)
+        {
+            await using var db = await DbFactory.CreateDbContextAsync();
+            _existing = await db.UnsAreas.AsNoTracking()
+                .FirstOrDefaultAsync(a => a.ClusterId == ClusterId && a.UnsAreaId == UnsAreaId);
+            if (_existing is not null)
+            {
+                _form = new FormModel
+                {
+                    UnsAreaId = _existing.UnsAreaId,
+                    Name = _existing.Name,
+                    Notes = _existing.Notes,
+                    RowVersion = _existing.RowVersion,
+                };
+            }
+        }
+        _loaded = true;
+    }
+
+    private async Task SubmitAsync()
+    {
+        _busy = true; _error = null;
+        try
+        {
+            await using var db = await DbFactory.CreateDbContextAsync();
+            if (IsNew)
+            {
+                if (await db.UnsAreas.AnyAsync(a => a.UnsAreaId == _form.UnsAreaId))
+                { _error = $"Area '{_form.UnsAreaId}' already exists."; return; }
+                db.UnsAreas.Add(new UnsArea
+                {
+                    UnsAreaId = _form.UnsAreaId,
+                    ClusterId = ClusterId,
+                    Name = _form.Name,
+                    Notes = string.IsNullOrWhiteSpace(_form.Notes) ? null : _form.Notes,
+                });
+            }
+            else
+            {
+                var entity = await db.UnsAreas.FirstOrDefaultAsync(
+                    a => a.ClusterId == ClusterId && a.UnsAreaId == UnsAreaId);
+                if (entity is null) { _error = "Row no longer exists."; return; }
+                db.Entry(entity).Property(e => e.RowVersion).OriginalValue = _form.RowVersion;
+                entity.Name = _form.Name;
+                entity.Notes = string.IsNullOrWhiteSpace(_form.Notes) ? null : _form.Notes;
+            }
+            await db.SaveChangesAsync();
+            Nav.NavigateTo($"/clusters/{ClusterId}/uns");
+        }
+        catch (DbUpdateConcurrencyException) { _error = "Another user changed this area while you were editing. Reload to see the latest values."; }
+        catch (Exception ex) { _error = ex.Message; }
+        finally { _busy = false; }
+    }
+
+    private async Task DeleteAsync()
+    {
+        if (IsNew) return;
+        _busy = true; _error = null;
+        try
+        {
+            await using var db = await DbFactory.CreateDbContextAsync();
+            var entity = await db.UnsAreas.FirstOrDefaultAsync(
+                a => a.ClusterId == ClusterId && a.UnsAreaId == UnsAreaId);
+            if (entity is null) { Nav.NavigateTo($"/clusters/{ClusterId}/uns"); return; }
+            db.Entry(entity).Property(e => e.RowVersion).OriginalValue = _form.RowVersion;
+            db.UnsAreas.Remove(entity);
+            await db.SaveChangesAsync();
+            Nav.NavigateTo($"/clusters/{ClusterId}/uns");
+        }
+        catch (DbUpdateConcurrencyException) { _error = "Another user changed this area while you were viewing it."; }
+        catch (Exception ex) { _error = $"Delete failed: {ex.Message}. Likely because lines still reference this area — remove them first."; }
+        finally { _busy = false; }
+    }
+
+    private sealed class FormModel
+    {
+        [Required, RegularExpression("^[A-Za-z0-9_-]+$")] public string UnsAreaId { get; set; } = "";
+        [Required] public string Name { get; set; } = "";
+        public string? Notes { get; set; }
+        public byte[] RowVersion { get; set; } = [];
+    }
+}

src/Server/ZB.MOM.WW.OtOpcUa.AdminUI/Components/Pages/Clusters/UnsLineEdit.razor

@@ -0,0 +1,187 @@
+@page "/clusters/{ClusterId}/uns/lines/new"
+@page "/clusters/{ClusterId}/uns/lines/{UnsLineId}"
+@attribute [Microsoft.AspNetCore.Authorization.Authorize]
+@rendermode RenderMode.InteractiveServer
+@using Microsoft.AspNetCore.Components.Forms
+@using Microsoft.EntityFrameworkCore
+@using System.ComponentModel.DataAnnotations
+@using ZB.MOM.WW.OtOpcUa.Configuration
+@using ZB.MOM.WW.OtOpcUa.Configuration.Entities
+@inject IDbContextFactory<OtOpcUaConfigDbContext> DbFactory
+@inject NavigationManager Nav
+
+<div class="d-flex justify-content-between align-items-center mb-3">
+    <h4 class="mb-0">@(IsNew ? "New UNS line" : "Edit UNS line") &middot; <span class="mono">@ClusterId</span></h4>
+    <a href="/clusters/@ClusterId/uns" class="btn btn-outline-secondary btn-sm">Cancel</a>
+</div>
+
+<ClusterNav ClusterId="@ClusterId" ActiveTab="uns" />
+
+@if (!_loaded)
+{
+    <p>Loading…</p>
+}
+else if (!IsNew && _existing is null)
+{
+    <section class="panel notice rise" style="animation-delay:.02s">
+        Line <span class="mono">@UnsLineId</span> was not found.
+    </section>
+}
+else
+{
+    <EditForm Model="_form" OnValidSubmit="SubmitAsync" FormName="unsLineEdit">
+        <DataAnnotationsValidator />
+        <section class="panel rise" style="animation-delay:.02s">
+            <div class="panel-head">UNS line (level 4)</div>
+            <div style="padding:1rem">
+                <div class="mb-3">
+                    <label class="form-label" for="lid">UnsLineId</label>
+                    <InputText id="lid" @bind-Value="_form.UnsLineId" disabled="@(!IsNew)"
+                               class="form-control form-control-sm mono" />
+                </div>
+                <div class="mb-3">
+                    <label class="form-label" for="area">Parent area</label>
+                    <InputSelect id="area" @bind-Value="_form.UnsAreaId" class="form-select form-select-sm">
+                        @foreach (var area in _areas)
+                        {
+                            <option value="@area.UnsAreaId">@area.UnsAreaId &mdash; @area.Name</option>
+                        }
+                    </InputSelect>
+                </div>
+                <div class="mb-3">
+                    <label class="form-label" for="name">Name</label>
+                    <InputText id="name" @bind-Value="_form.Name" class="form-control form-control-sm" />
+                </div>
+                <div class="mb-3">
+                    <label class="form-label" for="notes">Notes</label>
+                    <InputTextArea id="notes" @bind-Value="_form.Notes" class="form-control form-control-sm" rows="3" />
+                </div>
+            </div>
+        </section>
+
+        @if (!string.IsNullOrWhiteSpace(_error))
+        {
+            <div class="panel notice mt-3" style="border-color:var(--alert)">@_error</div>
+        }
+
+        <div class="mt-3 d-flex gap-2">
+            <button type="submit" class="btn btn-primary" disabled="@_busy">
+                @if (_busy) { <span class="spinner-border spinner-border-sm me-1"></span> }
+                @(IsNew ? "Create" : "Save changes")
+            </button>
+            <a href="/clusters/@ClusterId/uns" class="btn btn-outline-secondary">Cancel</a>
+            @if (!IsNew)
+            {
+                <button type="button" class="btn btn-outline-danger ms-auto" @onclick="DeleteAsync" disabled="@_busy">Delete</button>
+            }
+        </div>
+    </EditForm>
+}
+
+@code {
+    [Parameter] public string ClusterId { get; set; } = "";
+    [Parameter] public string? UnsLineId { get; set; }
+
+    private bool IsNew => string.IsNullOrEmpty(UnsLineId);
+
+    private FormModel _form = new();
+    private UnsLine? _existing;
+    private List<UnsArea> _areas = new();
+    private bool _loaded;
+    private bool _busy;
+    private string? _error;
+
+    protected override async Task OnInitializedAsync()
+    {
+        await using var db = await DbFactory.CreateDbContextAsync();
+        _areas = await db.UnsAreas.AsNoTracking()
+            .Where(a => a.ClusterId == ClusterId)
+            .OrderBy(a => a.UnsAreaId)
+            .ToListAsync();
+
+        if (!IsNew)
+        {
+            _existing = await db.UnsLines.AsNoTracking()
+                .FirstOrDefaultAsync(l => l.UnsLineId == UnsLineId);
+            if (_existing is not null)
+            {
+                _form = new FormModel
+                {
+                    UnsLineId = _existing.UnsLineId,
+                    UnsAreaId = _existing.UnsAreaId,
+                    Name = _existing.Name,
+                    Notes = _existing.Notes,
+                    RowVersion = _existing.RowVersion,
+                };
+            }
+        }
+        else
+        {
+            _form.UnsAreaId = _areas.FirstOrDefault()?.UnsAreaId ?? "";
+        }
+        _loaded = true;
+    }
+
+    private async Task SubmitAsync()
+    {
+        _busy = true; _error = null;
+        try
+        {
+            await using var db = await DbFactory.CreateDbContextAsync();
+            if (IsNew)
+            {
+                if (await db.UnsLines.AnyAsync(l => l.UnsLineId == _form.UnsLineId))
+                { _error = $"Line '{_form.UnsLineId}' already exists."; return; }
+                db.UnsLines.Add(new UnsLine
+                {
+                    UnsLineId = _form.UnsLineId,
+                    UnsAreaId = _form.UnsAreaId,
+                    Name = _form.Name,
+                    Notes = string.IsNullOrWhiteSpace(_form.Notes) ? null : _form.Notes,
+                });
+            }
+            else
+            {
+                var entity = await db.UnsLines.FirstOrDefaultAsync(l => l.UnsLineId == UnsLineId);
+                if (entity is null) { _error = "Row no longer exists."; return; }
+                db.Entry(entity).Property(e => e.RowVersion).OriginalValue = _form.RowVersion;
+                entity.UnsAreaId = _form.UnsAreaId;
+                entity.Name = _form.Name;
+                entity.Notes = string.IsNullOrWhiteSpace(_form.Notes) ? null : _form.Notes;
+            }
+            await db.SaveChangesAsync();
+            Nav.NavigateTo($"/clusters/{ClusterId}/uns");
+        }
+        catch (DbUpdateConcurrencyException) { _error = "Another user changed this line while you were editing."; }
+        catch (Exception ex) { _error = ex.Message; }
+        finally { _busy = false; }
+    }
+
+    private async Task DeleteAsync()
+    {
+        if (IsNew) return;
+        _busy = true; _error = null;
+        try
+        {
+            await using var db = await DbFactory.CreateDbContextAsync();
+            var entity = await db.UnsLines.FirstOrDefaultAsync(l => l.UnsLineId == UnsLineId);
+            if (entity is null) { Nav.NavigateTo($"/clusters/{ClusterId}/uns"); return; }
+            db.Entry(entity).Property(e => e.RowVersion).OriginalValue = _form.RowVersion;
+            db.UnsLines.Remove(entity);
+            await db.SaveChangesAsync();
+            Nav.NavigateTo($"/clusters/{ClusterId}/uns");
+        }
+        catch (DbUpdateConcurrencyException) { _error = "Another user changed this line while you were viewing it."; }
+        catch (Exception ex) { _error = $"Delete failed: {ex.Message}. Likely because equipment still references this line — remove or re-home it first."; }
+        finally { _busy = false; }
+    }
+
+    private sealed class FormModel
+    {
+        [Required, RegularExpression("^[A-Za-z0-9_-]+$")] public string UnsLineId { get; set; } = "";
+        [Required] public string UnsAreaId { get; set; } = "";
+        [Required] public string Name { get; set; } = "";
+        public string? Notes { get; set; }
+        public byte[] RowVersion { get; set; } = [];
+    }
+}