feat(dcl): bind OPC UA nodes by namespace URI, not baked index

A stored ns=<index> reference is only meaningful against one server's namespace
table. A server that adds, removes or reorders a namespace silently re-points
every binding: best case BadNodeIdUnknown, worst case the index now names a
different namespace holding a colliding identifier and the binding resolves to
the wrong node with Good quality. Nothing could detect that, because ScadaBridge
stored no namespace URI anywhere.

OtOpcUa v3.0 makes this concrete: v2's sole custom namespace and v3's raw
namespace both sit at index 2, so v2-era bindings resolve against v3 without
error while meaning something else entirely.

Adds OpcUaNodeReference as the single translation seam between stored references
and the wire. Resolve() accepts both ns=<index>;s=<id> (existing bindings, which
keep working unchanged) and the durable nsu=<uri>;s=<id>, mapping the URI to the
live index at use time; it is wired into every parse site — subscribe, read,
write, alarm-subscribe and browse. An unpublished URI now throws naming the URI
rather than binding to whatever occupies that index, and a svr= reference to
another server is rejected instead of being resolved against the wrong address
space.

The browser emits ToDurable(), so what the picker shows is what gets stored and
newly-authored bindings are index-proof from the start. That also closes a
round-trip gap: browse previously emitted ExpandedNodeId.ToString(), which for a
URI- or server-index-carrying reference produced a string NodeId.Parse could not
read back — the same method already resolved it correctly 57 lines later.

Bindings stored before this change keep their ns= form and keep working; they are
only as durable as the server's namespace order. Re-authoring against the picker
is what makes them durable, and that re-bind still needs a live v3 rig.

Refs: Gitea #14

src/ZB.MOM.WW.ScadaBridge.DataConnectionLayer/Adapters/RealOpcUaClient.cs

@@ -411,7 +411,7 @@ public class RealOpcUaClient : IOpcUaClient
         var monitoredItem = new MonitoredItem(_subscription.DefaultItem)
         {
             DisplayName = nodeId,
-            StartNodeId = nodeId,
+            StartNodeId = OpcUaNodeReference.Resolve(nodeId, _session.NamespaceUris),
             AttributeId = Attributes.Value,
             SamplingInterval = _options.SamplingIntervalMs,
             QueueSize = (uint)_options.QueueSize,
@@ -475,7 +475,9 @@ public class RealOpcUaClient : IOpcUaClient
         _alarmInRefresh[handle] = false;
         _alarmLastState[handle] = new Dictionary<string, (bool, bool)>(StringComparer.Ordinal);
 
-        var startNode = string.IsNullOrEmpty(sourceNodeId) ? ObjectIds.Server : NodeId.Parse(sourceNodeId);
+        var startNode = string.IsNullOrEmpty(sourceNodeId)
+            ? ObjectIds.Server
+            : OpcUaNodeReference.Resolve(sourceNodeId, _session.NamespaceUris);
         var item = new MonitoredItem(_subscription.DefaultItem)
         {
             DisplayName = $"alarm:{sourceNodeId ?? "Server"}",
@@ -829,7 +831,7 @@ public class RealOpcUaClient : IOpcUaClient
 
         var readValue = new ReadValueId
         {
-            NodeId = nodeId,
+            NodeId = OpcUaNodeReference.Resolve(nodeId, _session.NamespaceUris),
             AttributeId = Attributes.Value
         };
 
@@ -848,7 +850,7 @@ public class RealOpcUaClient : IOpcUaClient
 
         var writeValue = new WriteValue
         {
-            NodeId = nodeId,
+            NodeId = OpcUaNodeReference.Resolve(nodeId, _session.NamespaceUris),
             AttributeId = Attributes.Value,
             Value = new DataValue(new Variant(value))
         };
@@ -960,7 +962,7 @@ public class RealOpcUaClient : IOpcUaClient
         // an absolute NodeId expression.
         var nodeToBrowse = string.IsNullOrEmpty(parentNodeId)
             ? ObjectIds.ObjectsFolder
-            : NodeId.Parse(parentNodeId);
+            : OpcUaNodeReference.Resolve(parentNodeId, session.NamespaceUris);
 
         // No token → fresh browse of the node. A non-empty token → continue a
         // prior browse via BrowseNext, falling back to a fresh browse if the
@@ -1066,7 +1068,11 @@ public class RealOpcUaClient : IOpcUaClient
         foreach (var r in refs)
         {
             children.Add(new Commons.Interfaces.Protocol.BrowseNode(
-                NodeId: r.NodeId.ToString(),
+                // Durable nsu= form, not r.NodeId.ToString(): the raw ExpandedNodeId
+                // string can carry a namespace URI or server index that Resolve cannot
+                // read back, and a bare ns= index rots the moment the server's
+                // namespace table changes. What the picker shows is what gets stored.
+                NodeId: OpcUaNodeReference.ToDurable(r.NodeId, session.NamespaceUris),
                 DisplayName: r.DisplayName?.Text ?? r.BrowseName?.Name ?? "(unnamed)",
                 NodeClass: MapNodeClass(r.NodeClass),
                 HasChildren: r.NodeClass == NodeClass.Object));