refactor(app): compose interaction and retained UI startup

docs/architecture/code-structure.md

@@ -726,12 +726,16 @@ oracle, platform/host/content/settings phases, and the production world/render
 phase. `WorldRenderCompositionPhase` owns Region/environment, the mandatory
 modern-renderer foundation, immutable terrain-worker inputs, and WB/texture/
 sampler construction; every Phase-4 GL constructor has retryable prefix
-ownership. `GameWindow` is 3,522 raw lines after I.5. Checkpoints I.6–L remain
-active, with retained UI and live presentation composition next. The current
-production App build is warning-free; the App gate passes 3,373 tests / 3
-intentional skips and the complete Release suite passes 7,745 tests / 5
-intentional skips. I.5's corrected-diff behavior, architecture, and
-adversarial reviews are clean.
+ownership. `GameWindow` is 3,522 raw lines after I.5. I.6a moves interaction
+and retained-UI construction into `InteractionRetainedUiCompositionPhase`;
+typed exact-owner sources now bridge the later session, selection, radar,
+view-plane, diagnostics, inventory, and automation owners without callbacks to
+the window. The old item-use and selection wrapper methods are deleted.
+`GameWindow` is 3,246 raw lines after I.6a. I.6b–L remain active, with live
+presentation and landblock-publication composition next. The App gate passes
+3,401 tests / 3 intentional skips and the complete Release suite passes 7,773
+tests / 5 intentional skips. The solution retains only the 17 warnings tracked
+by #228; the I.6a behavior, architecture, and adversarial reviews are clean.
 
 ### 4.4 Exit criteria
 

docs/plans/2026-07-22-gamewindow-slice-8-checkpoint-i-ordered-composition.md

@@ -274,6 +274,12 @@ ledger only after the complete pipeline is live.
 - I.6 (retained UI plus live-presentation composition) is active. Its detailed
   two-commit ownership and failure-test plan is
   [`2026-07-22-gamewindow-slice-8-checkpoint-i6-ui-live-presentation.md`](2026-07-22-gamewindow-slice-8-checkpoint-i6-ui-live-presentation.md).
+  I.6a is complete: Phase 5 now composes interaction and retained UI through
+  typed dependencies, exact-owner late bindings, and transactional rollback.
+  `GameWindow.cs` is 3,246 raw lines; the App gate passes 3,401 tests / 3
+  intentional skips and the complete Release suite passes 7,773 tests / 5
+  intentional skips. I.6b live presentation and landblock publication is the
+  active cut.
   Checkpoint I remains active until I.9 closes the complete nine-phase pipeline.
 
 ## 6. Automated acceptance

docs/plans/2026-07-22-gamewindow-slice-8-checkpoint-i6-ui-live-presentation.md

@@ -1,6 +1,6 @@
 # GameWindow Slice 8 — Checkpoint I.6 UI and Live Presentation
 
-**Status:** Active
+**Status:** I.6a complete; I.6b active
 
 **Parent:** `2026-07-22-gamewindow-slice-8-checkpoint-i-ordered-composition.md`
 
@@ -73,8 +73,9 @@ Deactivation makes all callbacks inert before runtime teardown.
 ### 2.3 Ownership and publication
 
 `InteractionRetainedUiResult` carries the stable owners required by later
-phases. `InteractionRetainedUiCompositionOwner` owns optional retained-UI
-input/runtime resources and the late authorities. Construction uses
+phases. `InteractionUiLateBindings` owns the retained input-capture lease and
+the late authorities; `RetailUiRuntimeLease` remains the sole owner of the
+optional host/runtime resources. Construction uses
 `CompositionAcquisitionScope`; the owner is published only after all mandatory
 interaction resources and every enabled retained-UI resource are complete.
 
@@ -82,13 +83,12 @@ interaction resources and every enabled retained-UI resource are complete.
 needed by existing steady-state and reset code. Publication is write-only and
 rejects replacement.
 
-Normal shutdown and construction rollback share these stages:
+Normal shutdown and construction rollback preserve these stages:
 
-1. deactivate late sources and retained input;
-2. detach retained UI device callbacks;
-3. dispose mounted runtime;
-4. dispose host/assets/probe resources;
-5. dispose item/external-container/combat owners.
+1. deactivate late sources and release retained input capture;
+2. dispose the retained-UI lease, which detaches device callbacks, the mounted
+   runtime, and the host in its established order;
+3. dispose item/external-container/combat owners.
 
 The existing retained UI lease remains the sole host/runtime owner until its
 full lifecycle is migrated; the phase owner controls it but never duplicates
@@ -110,6 +110,22 @@ its resources.
 - three independent self-review passes: retail behavior, architecture and
   ownership, adversarial failure/reentrancy.
 
+### 2.5 I.6a completion evidence
+
+I.6a moved the complete Phase-5 body into
+`InteractionRetainedUiCompositionPhase`. Exact-owner leases now guard retained
+input capture plus the late session, selection, radar, view-plane, diagnostics,
+inventory, and automation bindings. The old `GameWindow` item-use/pick/query
+wrappers are deleted; shared Vitals identity, mouse-before-keyboard ordering,
+direct contained-item use, and the disabled-retail-UI path remain unchanged.
+
+The focused success/failure/rollback matrix passes 28 tests. The App Release
+gate passes 3,401 tests / 3 intentional skips, the complete Release suite
+passes 7,773 tests / 5 intentional skips, and the solution build has only the
+17 warnings already tracked by #228. `GameWindow.cs` is 3,246 raw lines after
+I.6a. Behavior, ownership, and adversarial self-reviews found no remaining
+actionable issue. I.6b is the next active cut.
+
 ## 3. I.6b — live presentation and landblock publication
 
 ### 3.1 Owned construction