1f261263b2
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.