feat(v3-batch3): B3-WP4 — {{equip}}/<RefName> reference-relative resolution

Replace the deleted equipment-base-prefix {{equip}} mechanism (impossible now
that equipment is reference-only) with per-reference resolution:
{{equip}}/<RefName> resolves through the owning equipment's UnsTagReference rows
(by effective name) to the backing raw tag's RawPath. Every unresolved <RefName>
is a clear deploy error + authoring rejection + Monaco diagnostic — preserving
"editor accepts <=> publish accepts".

Commons:
- EquipmentScriptPaths: delete DeriveEquipmentBase; SubstituteEquipmentToken now
  takes the equipment's reference map (effectiveName -> RawPath) and substitutes
  {{equip}}/<RefName> inside path literals (unresolved left intact, never throws);
  add ExtractEquipReferenceNames (path-literal scoped) +
  ExtractEquipReferenceNamesFromText (message templates). Slash syntax replaces
  the v2 dot joint.
- New EquipmentReferenceMap: shared, input-shape-agnostic builder (entity + JSON
  sides) over RawPathResolver — the single authority both compose seams + the
  validator use, so resolved RawPaths agree byte-for-byte.

Compose seams (byte-parity kept):
- AddressSpaceComposer.Compose + DeploymentArtifact.ParseComposition both build
  the per-equipment reference map from UnsTagReferences + Tags + raw topology and
  substitute VirtualTag AND ScriptedAlarm-predicate sources before dependency
  extraction (runtime dep refs = resolved RawPaths).

Deploy gate + authoring + editor:
- DraftValidator.ValidateEquipReferenceResolution: EquipReferenceUnresolved error
  for unresolved {{equip}}/<RefName> in VirtualTag/ScriptedAlarm scripts + alarm
  message-template tokens (naming script, equipment, missing ref).
- UnsTreeService.ValidateEquipTokenAsync (Wave-A M1): reference-relative authoring
  rejection, replacing the stale DeriveEquipmentBase(empty)->reject-all logic.
- ScriptAnalysisService: {{equip}}/ completion offers the equipment's reference
  effective names; DiagnoseAsync flags unresolved refs (OTSCRIPT_EQUIPREF) same as
  the deploy gate. Requests carry optional EquipmentId (threaded MonacoEditor ->
  monaco-init.js -> fetch bodies). IScriptTagCatalog.GetEquipmentRelativeLeavesAsync
  repurposed to GetEquipmentReferenceNamesAsync(equipmentId, filter).

Tests: EquipmentScriptPaths substitution/extraction (slash pinned); composer<->
artifact reference-resolution byte-parity; DraftValidator unresolved-ref;
ScriptAnalysis completion+diagnostic; M1 authoring gate. Build clean (0/0); all
five affected suites green.

Claude-Session: https://claude.ai/code/session_01LVneM3eh1UtJxEisFXgmox

src/Server/ZB.MOM.WW.OtOpcUa.AdminUI/Uns/UnsTreeService.cs

@@ -866,29 +866,45 @@ public sealed class UnsTreeService(IDbContextFactory<OtOpcUaConfigDbContext> dbF
     }
 
     /// <summary>
-    /// When the bound script uses the reserved <c>{{equip}}</c> token, the owning equipment must have
-    /// a derivable tag base (≥1 driver tag, all sharing one object prefix). Returns a rejection result
-    /// when the token is present but no base can be derived; <c>null</c> otherwise (token absent, or a
-    /// base exists). The script source is fetched from the supplied (in-scope) context.
+    /// v3 (M1): when the bound script uses <c>{{equip}}/&lt;RefName&gt;</c>, every <c>&lt;RefName&gt;</c> must
+    /// resolve to one of the owning equipment's <c>UnsTagReference</c> effective names (its
+    /// <c>DisplayNameOverride</c> else the backing raw tag's <c>Name</c>) — the same set the compose seams
+    /// substitute against and the deploy gate (<c>DraftValidator.ValidateEquipReferenceResolution</c>)
+    /// enforces. Returns a readable rejection naming the missing ref(s) when any is unresolved; <c>null</c>
+    /// otherwise (no slash-token, or all resolve). Replaces the v2 <c>DeriveEquipmentBase(empty)→null</c>
+    /// check, which rejected ALL <c>{{equip}}</c> VirtualTags with a now-impossible "add a driver tag" message.
     /// </summary>
     private static async Task<UnsMutationResult?> ValidateEquipTokenAsync(
         OtOpcUaConfigDbContext db, string equipmentId, string scriptId, CancellationToken ct)
     {
         var src = await db.Scripts.Where(s => s.ScriptId == scriptId)
             .Select(s => s.SourceCode).FirstOrDefaultAsync(ct);
-        if (!EquipmentScriptPaths.ContainsEquipToken(src)) return null;
+        var used = EquipmentScriptPaths.ExtractEquipReferenceNames(src);
+        if (used.Count == 0) return null;
 
-        // The equipment↔Tag binding was retired in v3 (Tag is Raw-only), so no equipment-bound driver
-        // tags exist to derive an equipment tag base from. The {{equip}} token can't be resolved here.
-        var fullNames = Array.Empty<string>();
-        if (EquipmentScriptPaths.DeriveEquipmentBase(fullNames) is null)
+        // The equipment's reference effective-name set: DisplayNameOverride else the backing raw tag's Name.
+        var refs = await db.UnsTagReferences.AsNoTracking()
+            .Where(r => r.EquipmentId == equipmentId)
+            .Select(r => new { r.TagId, r.DisplayNameOverride })
+            .ToListAsync(ct);
+        var tagIds = refs.Select(r => r.TagId).ToList();
+        var tagNameById = await db.Tags.AsNoTracking()
+            .Where(t => tagIds.Contains(t.TagId))
+            .Select(t => new { t.TagId, t.Name })
+            .ToDictionaryAsync(t => t.TagId, t => t.Name, ct);
+        var effectiveNames = new HashSet<string>(StringComparer.Ordinal);
+        foreach (var r in refs)
         {
-            return new UnsMutationResult(false,
-                $"Equipment '{equipmentId}' has no single tag base, so the "
-                + $"{EquipmentScriptPaths.EquipToken} token can't be resolved. Add at least one driver tag under this "
-                + $"equipment (all sharing one object prefix), or remove {EquipmentScriptPaths.EquipToken} from the script.");
+            var eff = r.DisplayNameOverride ?? (tagNameById.TryGetValue(r.TagId, out var n) ? n : null);
+            if (!string.IsNullOrEmpty(eff)) effectiveNames.Add(eff!);
         }
-        return null;
+
+        var missing = used.Where(u => !effectiveNames.Contains(u)).ToList();
+        if (missing.Count == 0) return null;
+        return new UnsMutationResult(false,
+            $"Script uses {string.Join(", ", missing.Select(m => $"'{EquipmentScriptPaths.EquipTokenPrefix}{m}'"))} "
+            + $"but equipment '{equipmentId}' has no reference with that effective name. "
+            + "Add a matching reference on the Tags tab, or correct the script.");
     }
 
     /// <inheritdoc />