docs(runtime): close interaction transaction ownership

Record the exact J5.2 owner boundary, retail ordering, Release and connected evidence, rollback, and J5.3 handoff across architecture, roadmap, milestones, agent instructions, and durable memory.

Co-authored-by: Codex <noreply@openai.com>

docs/research/2026-07-26-slice-j5-2-interaction-transactions.md

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+# Slice J5.2 — canonical interaction transactions
+
+**Date:** 2026-07-26
+**Production commit:** `f5f7b4177f449ebcad9724bfea263ef73ab60255`
+**Parent plan:** `docs/plans/2026-07-26-modern-runtime-slice-j5.md`
+
+## Result
+
+Interaction transaction authority now lives beneath the canonical Runtime
+action root. `RuntimeInteractionTransactionState` owns:
+
+- retail's strict 200-ms local use throttle;
+- last ordinary or targeted-use source/target identity;
+- pending and current appraisal identity;
+- the typed frame-ordered Activate/Use/Pickup FIFO;
+- the exact pending pickup identity, inventory-placement token, and
+  post-arrival movement token;
+- reset, disposal, failure, and ownership accounting.
+
+It borrows the exact `RuntimeInventoryState.Transactions` instance. There is no
+second busy counter, inventory request, object table, or pending-pickup
+authority.
+
+App remains the graphical adapter. It performs world picking, selection
+lighting, approach installation, wire transport, toasts, retained drag/drop,
+and pending-slot drawing. The former App `OutboundInteractionQueue` and the
+use/appraisal/pickup transaction fields in App controllers are deleted.
+
+## Retail order preserved
+
+The implementation preserves the named-retail order recorded in
+`docs/research/2026-07-26-slice-j5-owner-and-retail-order-inventory.md`:
+
+- `ItemHolder::UseObject @ 0x00588A80` applies the strict local use gate,
+  emits ordinary Use immediately after policy accepts it, and transfers one
+  shared UI-busy reference to the server completion;
+- `ClientUISystem::Handle_Item__UseDone @ 0x00564900` releases exactly one
+  busy reference;
+- targeted Use stores the source until a compatible target is acquired, then
+  emits the exact source/target pair;
+- pickup alone retains the existing local approach transaction and sends once
+  after the exact natural completion token.
+
+No new polling, background thread, asynchronous command seam, speculative
+approach for ordinary Use, or frame of gameplay latency was introduced.
+
+## Lifetime and failure behavior
+
+- Queued work carries server GUID, optional exact Runtime local ID, and
+  optional exact `ClientObject` identity.
+- Hidden cancels every queued/deferred transaction for that server object.
+- Deletion cancels only the removed local incarnation, so GUID reuse cannot
+  erase or execute replacement work.
+- A captured frame drains in FIFO order; re-entrant additions wait for the
+  next frame.
+- Re-entrant reset/disposal stops the captured suffix and cannot resurrect
+  targeted-use or pickup state.
+- Appraisal transport failure rolls back only the busy reference acquired by
+  that exact request.
+- A dispatched ordinary Use remains busy until authoritative UseDone; later
+  movement cancellation, Hidden, or deletion cannot retract or duplicate its
+  packet.
+- Runtime action disposal precedes inventory disposal because the transaction
+  child borrows the exact inventory gate.
+
+## Automated gates
+
+All commands ran in Release:
+
+- `dotnet test tests/AcDream.Runtime.Tests/AcDream.Runtime.Tests.csproj`:
+  197 passed.
+- `dotnet test tests/AcDream.App.Tests/AcDream.App.Tests.csproj`:
+  3,775 passed / 3 fixture-generator skips.
+- `dotnet build AcDream.slnx -c Release --no-restore`: passed.
+- `dotnet test AcDream.slnx -c Release --no-build --no-restore`:
+  8,561 passed / 5 established skips.
+- `git diff --check`: passed.
+
+Focused tests cover the 199/200-ms throttle boundary, ordinary and targeted
+Use, UseDone, appraisal replacement/refresh/failure, typed FIFO and re-entrant
+drain, Hidden/delete cancellation, exact approach completion, transport
+failure, pending-slot acceptance/failure, GUID reuse, reset/disposal, and
+two-instance isolation.
+
+## Exact-binary connected gate
+
+Report:
+`logs/connected-world-gate-20260726-111330/report.json`.
+
+The report identifies exact source/binary commit
+`f5f7b4177f449ebcad9724bfea263ef73ab60255` and passes:
+
+- six capped login/outdoor/world-edge/dungeon/revisit checkpoints;
+- one fresh uncapped-process reconnect checkpoint;
+- 7/7 complete reveal/readiness checkpoints;
+- zero invariant failures and zero render-scene mismatches;
+- 243.534-second capped and 61.619-second reconnect sessions;
+- graceful logout and code-zero exit for both processes;
+- zero failures;
+- one expected warning covering 25 empty world-edge landblocks.
+
+## Divergence audit
+
+This is an ownership-only move of accepted retail-faithful behavior. It adds
+no approximation, alternate algorithm, polling mirror, or asynchronous seam.
+No divergence-register row was added or retired.
+
+## Rollback
+
+```text
+git revert f5f7b4177f449ebcad9724bfea263ef73ab60255
+```
+
+Revert J5 sub-slices in reverse order. Do not revert J4's canonical inventory
+owner or Slice I's flat-collision cutover to mask a later action-owner defect.
+
+## Next boundary
+
+J5.3 moves combat attack and spell-cast intent into Runtime. App continues to
+own the combat/spell widgets, camera tracking, animations, audio, particles,
+DAT catalog/icon/formula presentation, and response text.