feat(m9/T24b): move-data-connection UI dialog + action

src/ZB.MOM.WW.ScadaBridge.CentralUI/Components/Pages/Design/DataConnections.razor

@@ -42,6 +42,12 @@
 
     <ToastNotification @ref="_toast" />
 
+    <MoveDataConnectionDialog @bind-IsVisible="_showMoveDialog"
+                              ConnectionId="_moveConnectionId"
+                              ConnectionName="@_moveConnectionName"
+                              SiteOptions="MoveTargetSiteOptions()"
+                              OnMoved="OnConnectionMoved" />
+
     @if (_loading)
     {
         <LoadingSpinner IsLoading="true" />
@@ -124,6 +130,12 @@
                                         Edit
                                     </button>
                                 </li>
+                                <li>
+                                    <button class="dropdown-item"
+                                            @onclick="() => OpenMoveDialog(node.Connection!)">
+                                        Move to Site…
+                                    </button>
+                                </li>
                                 <li><hr class="dropdown-divider" /></li>
                                 <li>
                                     <button class="dropdown-item text-danger"
@@ -150,6 +162,10 @@
                             @onclick='() => NavigationManager.NavigateTo($"/design/connections/{node.Connection!.Id}/edit")'>
                         Edit
                     </button>
+                    <button class="dropdown-item"
+                            @onclick="() => OpenMoveDialog(node.Connection!)">
+                        Move to Site…
+                    </button>
                     <div class="dropdown-divider"></div>
                     <button class="dropdown-item text-danger"
                             @onclick="() => DeleteConnection(node.Connection!)">
@@ -409,6 +425,38 @@
         }
     }
 
+    // ── M9-T24b: Move connection to another site ──
+    // The dialog dispatches MoveDataConnectionCommand through the guard-running
+    // ManagementActor path (IDataConnectionMoveService) — NOT a direct repository
+    // write — so the server enforces the Designer gate and every move guard. The
+    // page only opens the dialog, supplies the candidate target sites (the current
+    // site excluded), and reloads the tree once the move succeeds.
+    private bool _showMoveDialog;
+    private int _moveConnectionId;
+    private int _moveConnectionSiteId;
+    private string _moveConnectionName = string.Empty;
+
+    private void OpenMoveDialog(DataConnection conn)
+    {
+        _moveConnectionId = conn.Id;
+        _moveConnectionSiteId = conn.SiteId;
+        _moveConnectionName = conn.Name;
+        _showMoveDialog = true;
+    }
+
+    // Candidate target sites for the move: every site EXCEPT the connection's
+    // current one. Sourced from the already-loaded tree roots (each root is a site).
+    private IEnumerable<(int Id, string Label)> MoveTargetSiteOptions() =>
+        _treeRoots
+            .Where(r => r.SiteId is int sid && sid != _moveConnectionSiteId)
+            .Select(r => (r.SiteId!.Value, r.Label));
+
+    private async Task OnConnectionMoved()
+    {
+        _toast.ShowSuccess($"Connection '{_moveConnectionName}' moved.");
+        await LoadDataAsync();
+    }
+
     // M9-T25: enum → Bootstrap badge class. Mirrors the Health dashboard's
     // GetConnectionHealthBadge (Components/Pages/Monitoring/Health.razor) so the
     // design page surfaces the same colour coding for the same status. Kept as a

src/ZB.MOM.WW.ScadaBridge.CentralUI/Components/Shared/MoveDataConnectionDialog.razor

@@ -0,0 +1,105 @@
+@using ZB.MOM.WW.ScadaBridge.CentralUI.Services
+@inject IDataConnectionMoveService MoveService
+
+@*
+    M9-T24b: Move a data connection to another site. The picker lists the candidate
+    target sites (the page excludes the connection's current site). On confirm the
+    dialog dispatches MoveDataConnectionCommand through IDataConnectionMoveService —
+    the guard-running ManagementActor path, NOT a direct repository write — so the
+    server's Designer gate and every move guard (target exists, no name collision, no
+    instance binding, no native-alarm-source name reference) run. A guard error is
+    shown inline and the dialog stays open; success closes the dialog and raises
+    OnMoved so the page reloads the tree. Mirrors the MoveFolderDialog idiom.
+*@
+@if (IsVisible)
+{
+    <div class="modal show d-block" tabindex="-1" style="background: rgba(0,0,0,0.4);">
+        <div class="modal-dialog">
+            <div class="modal-content">
+                <div class="modal-header">
+                    <h6 class="modal-title">Move '@ConnectionName' to site…</h6>
+                    <button type="button" class="btn-close" @onclick="Close" disabled="@_busy"></button>
+                </div>
+                <div class="modal-body">
+                    @if (SiteOptions.Any())
+                    {
+                        <select class="form-select form-select-sm" @bind="_targetSiteId">
+                            @foreach (var opt in SiteOptions)
+                            {
+                                <option value="@opt.Id">@opt.Label</option>
+                            }
+                        </select>
+                    }
+                    else
+                    {
+                        <div class="text-muted small">No other site is available to move this connection to.</div>
+                    }
+                    @if (!string.IsNullOrEmpty(_error))
+                    {
+                        <div class="text-danger small mt-2" data-test="move-connection-error">@_error</div>
+                    }
+                </div>
+                <div class="modal-footer">
+                    <button class="btn btn-outline-secondary btn-sm" @onclick="Close" disabled="@_busy">Cancel</button>
+                    <button class="btn btn-primary btn-sm" @onclick="Submit"
+                            disabled="@(_busy || !SiteOptions.Any())">Move</button>
+                </div>
+            </div>
+        </div>
+    </div>
+}
+
+@code {
+    [Parameter] public bool IsVisible { get; set; }
+    [Parameter] public EventCallback<bool> IsVisibleChanged { get; set; }
+    [Parameter] public int ConnectionId { get; set; }
+    [Parameter] public string ConnectionName { get; set; } = string.Empty;
+    [Parameter] public IEnumerable<(int Id, string Label)> SiteOptions { get; set; } = Array.Empty<(int, string)>();
+
+    /// <summary>Raised after a successful move so the page can reload the tree.</summary>
+    [Parameter] public EventCallback OnMoved { get; set; }
+
+    private bool _wasVisible;
+    private int? _targetSiteId;
+    private string? _error;
+    private bool _busy;
+
+    protected override void OnParametersSet()
+    {
+        // Reset internal state on transition from hidden -> visible: default the
+        // picker to the first candidate site and clear any prior error.
+        if (IsVisible && !_wasVisible)
+        {
+            _targetSiteId = SiteOptions.Select(o => (int?)o.Id).FirstOrDefault();
+            _error = null;
+            _busy = false;
+        }
+        _wasVisible = IsVisible;
+    }
+
+    private async Task Close()
+    {
+        await IsVisibleChanged.InvokeAsync(false);
+    }
+
+    private async Task Submit()
+    {
+        if (_targetSiteId is not int target || _busy) return;
+
+        _busy = true;
+        _error = null;
+        var result = await MoveService.MoveAsync(ConnectionId, target);
+        _busy = false;
+
+        if (result.Success)
+        {
+            await IsVisibleChanged.InvokeAsync(false);
+            await OnMoved.InvokeAsync();
+        }
+        else
+        {
+            // Surface the server guard error inline; keep the dialog open.
+            _error = result.Error ?? "Move failed.";
+        }
+    }
+}