fix(centralui): surface inherited compositions in the templates tree (followup #9)

The templates tree rendered a derived/composed member (e.g. LeftReactorSide,
derived from ReactorSide) as a flat leaf, omitting compositions it inherits
from its base (e.g. LeakTest composed onto ReactorSide). BuildCompositionLeavesFor
recursed only over a template's OWN composition rows; an inherited composition
row lives on the ancestor, and TemplateComposition has no IsInherited placeholder
(unlike attributes/alarms/scripts/native-sources), so the child's own Compositions
was empty. Same 'derived templates don't surface inherited members' family as
followups #1/#2, but for compositions. Deploy/flatten was always correct
(TemplateResolver.ResolveAllMembers walks the chain) — display-only.

Fix:
- BuildCompositionLeavesFor now renders the EFFECTIVE composition set (own +
  inherited) via EffectiveCompositionsFor, which walks the inheritance chain
  (leaf->root, child wins on InstanceName), mirroring the resolver.
- Inherited slots are flagged (TemplateTreeNode.IsInherited), badged 'inherited'
  in the label, and their context menu offers only 'Open composed template'
  (Rename/Delete edit the ancestor's slot, so suppressed on inherited nodes).
- The same inherited row can appear under several derived members (LeakTest under
  both LeftReactorSide and RightReactorSide), so composition nodes use a
  path-qualified KeyOverride to keep TreeView selection/expansion keys unique;
  recursion is cycle-guarded.

Tests: +1 bUnit (TemplatesPageTests.Renders_InheritedComposition_UnderDerivedComposedMember);
CentralUI suite 867 green; full solution builds 0/0.

Docs: Component-CentralUI.md (effective composition set in tree); known-issues
tracker #9 recorded + resolved.

Note: CentralUI change — shows on wonder-app-vd03 only after that host is redeployed.

tests/ZB.MOM.WW.ScadaBridge.CentralUI.Tests/TemplatesPageTests.cs

@@ -129,6 +129,51 @@ public class TemplatesPageTests : BunitContext
         Assert.Contains("bi-arrow-return-right", cut.Markup);
     }
 
+    [Fact]
+    public void Renders_InheritedComposition_UnderDerivedComposedMember()
+    {
+        // followup #9: LeakTest is composed onto the BASE ReactorSide. LeftReactorSide is
+        // DERIVED from ReactorSide and composed into CvdReactor, so the tree must surface
+        // the INHERITED LeakTest slot under LeftReactorSide — the composition row lives on
+        // ReactorSide (no IsInherited placeholder on the child), so the builder must use
+        // the effective (own + inherited) composition set, mirroring the resolver.
+        var leakTest = new Template("LeakTest") { Id = 50 };
+        var reactorSide = new Template("ReactorSide") { Id = 7 };
+        reactorSide.Compositions.Add(
+            new TemplateComposition("LeakTest") { Id = 100, TemplateId = 7, ComposedTemplateId = 50 });
+        var leftReactorSide = new Template("LeftReactorSide") { Id = 8, ParentTemplateId = 7, IsDerived = true };
+        var cvdReactor = new Template("CvdReactor") { Id = 1 };
+        cvdReactor.Compositions.Add(
+            new TemplateComposition("LeftReactorSide") { Id = 200, TemplateId = 1, ComposedTemplateId = 8 });
+
+        _repo.GetAllTemplatesAsync(Arg.Any<CancellationToken>())
+            .Returns(Task.FromResult<IReadOnlyList<Template>>(
+                new List<Template> { cvdReactor, reactorSide, leftReactorSide, leakTest }));
+        _repo.GetAllFoldersAsync(Arg.Any<CancellationToken>())
+            .Returns(Task.FromResult<IReadOnlyList<TemplateFolder>>(new List<TemplateFolder>()));
+
+        var cut = Render<TemplatesPage>();
+
+        // Expand CvdReactor to reveal its composed member LeftReactorSide.
+        cut.FindAll("li[role='treeitem']")
+            .First(li => li.QuerySelector(".tv-label")?.TextContent.Trim() == "CvdReactor")
+            .QuerySelector(".tv-toggle")!.Click();
+
+        // LeftReactorSide must be expandable: before the fix it was a flat leaf with no
+        // toggle because its own Compositions are empty (LeakTest is inherited, not owned).
+        var leftLi = cut.FindAll("li[role='treeitem']")
+            .First(li => li.QuerySelector(".tv-label")?.TextContent.Trim() == "LeftReactorSide");
+        var leftToggle = leftLi.QuerySelector(".tv-toggle");
+        Assert.NotNull(leftToggle);
+        leftToggle!.Click();
+
+        // The inherited LeakTest slot now renders under LeftReactorSide, badged "inherited".
+        var leftLiAfter = cut.FindAll("li[role='treeitem']")
+            .First(li => li.QuerySelector(".tv-label")?.TextContent.Trim() == "LeftReactorSide");
+        Assert.Contains("LeakTest", leftLiAfter.TextContent);
+        Assert.Contains("inherited", leftLiAfter.TextContent);
+    }
+
     [Fact]
     public void SearchBox_IsPresentAndBound_ToTemplateFolderTreeFilter()
     {