docs: next-agent handoff prompt for the collision/placement regressions

Self-contained task brief: P1 retirement-receipt exception loop, P2
feel-test placement failures, P3 soak residuals re-judgment, P4 door
approach regression, P5 spell-particle deferral, P6 re-verifications;
process, gates, and commit rules included.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docs/research/2026-08-02-collision-throughput-handoff/NEXT-AGENT-PROMPT.md

@@ -0,0 +1,155 @@
+# Task: diagnose and fix the acdream collision/placement regressions, then COMMIT the fixes
+
+Work EXCLUSIVELY in `C:\Users\erikn\.codex\worktrees\af5e\acdream`, branch
+`codex/port-claude-agents`, HEAD `71604331`. Read `CLAUDE.md` at the repo
+root FIRST — its rules bind you (grep-named-retail-first workflow, no
+workarounds, divergence-register bookkeeping, connected gates, launch
+instructions). The user's in-game observations quoted below are AXIOMS —
+they override any green gate number.
+
+## Standing constraints
+
+- NEVER `git add -A`, `git add .`, `git reset --hard`, or
+  `git checkout -- <path>`. Stage exact paths only.
+- NEVER stage, revert, or normalize these user-local files: `AGENTS.md`,
+  `src/AcDream.App/Interaction/PlayerInteractionMovementSink.cs`,
+  `src/AcDream.App/Rendering/LiveAnimationPresentationContext.cs`,
+  `src/AcDream.Runtime/Physics/RuntimeRemotePhysicsUpdater.cs`,
+  `tests/AcDream.Core.Tests/Physics/CellTransitTests.cs`,
+  `tests/AcDream.Core.Tests/Physics/Issue133DungeonTeleportPrefixTests.cs`,
+  `tools/A8CellAudit/A8CellAudit.csproj`, the root
+  `implementer-progress.md`, and any `launch-*.log`.
+- No workarounds without explicit user approval: root causes only — no
+  rate knobs, grace periods, suppression flags, or catch-and-swallow.
+- Do not push. Commit locally to `codex/port-claude-agents` only.
+- Connected gates need the user's ACE server at `127.0.0.1:9000`
+  (normally up). Follow CLAUDE.md's "Logout-before-reconnect" graceful-
+  close discipline between client launches. If ACE is unreachable, STOP
+  and report — never fake or skip a connected gate.
+
+## Where everything is
+
+- **This directory** (`docs/research/2026-08-02-collision-throughput-handoff/`):
+  `design-note.md` (the approved D2 delta-commit design),
+  `implementer-progress.md` (the complete campaign evidence trail — read
+  the `## Collision-clone O1/O2/O3` and `## C3c-F4` sections first),
+  `docs-drafts.md` (register/digest drafts NOT yet applied),
+  `user-observations-*.md` (the axioms).
+- Campaign plan: `docs/plans/2026-08-02-placement-cutover.md`. C3c
+  closeout: `docs/research/2026-08-02-c3c-cutover-closeout.md`. Issues:
+  `docs/ISSUES.md` #276–#279.
+- Recent commits: `529e0e9d` (C3c production placement cutover — REVIEWED
+  and accepted), `f4ef2b2a`/`c52ce14a` (docs), `71604331` (the O1–O3
+  collision delta-commit — **WIP, ON HOLD, NO review passed it**; its
+  commit message summarizes state).
+- Logs (untracked): `launch-feeltest-oclone.log` (the FAILING user feel
+  test on the O-tree), `logs/connected-r6-soak-20260802-194423.*`
+  (current soak: Passed=false, 4 failures),
+  `logs/connected-r6-soak-20260802-143157.*` (pre-O soak: 37 failures),
+  `logs/connected-r6-soak-20260727-004942.artifacts` (last fully-PASSING
+  baseline), `logs/connected-world-gate-20260802-193029` (lifecycle PASS
+  on the O-tree).
+
+## Problems to diagnose and fix (priority order)
+
+**P1 — the retirement-receipt exception loop (smoking gun).**
+`launch-feeltest-oclone.log` contains **243** occurrences of
+`streaming: origin-recenter preparation will resume:
+System.InvalidOperationException: Landblock <id> already has a full
+retirement receipt.` — a continuous catch-retry loop during origin
+recenter. Find the receipt-lifecycle break introduced (or exposed) by
+the O1–O3 diff (`git show 71604331`): the retirement machinery is
+`RuntimePhysicsState.AdvanceCollisionRetirementMutation` (~:1880-1990),
+`StreamingController.cs` `AdvanceRetirements` call sites (:648/:670/:689/:736),
+recenter adoption at `LandblockPresentationPipeline.cs:322-345`. The
+catch-and-resume site that swallows this exception may itself violate
+the no-silent-catch rule — evaluate it too.
+
+**P2 — user-visible placement failures on the O-tree (the axioms).**
+Quote: "Monsters pop into existence as I run by them. ran to a different
+place, spawned in the air long in front of me, stabs are placed
+incorrectly. This is not how retail worked. I could see monsters way in
+front of me." Suspects, in order: (a) P1's stalled/looping recenter
+preparation starving placement; (b) the commit-time reflood diverging
+from the deleted staged-clone world in live conditions
+(`PhysicsEngine.CommitLandblockReplacement` +
+`RefloodPrefixOwnersAfterReplacement`; the oracle test
+`CommitTimeRefloodMatchesPrecomputedReflood` covers only 3 landblock
+archetypes and may under-cover); (c) siblings of the staged-owner
+admission gap the implementer already fixed once (ShadowObjectRegistry
+phase 2); (d) ordering between the reflood and admission
+commit/RetryDeferred for operations parked on the republished prefix.
+Note: under C3c rules entities WAIT for collision before placing — so
+"spawned mid-air" means placement completed against wrong/incomplete
+collision, not merely late.
+
+**P3 — the soak's 4 remaining failures.**
+`connected-r6-soak-20260802-194423.report.json`:
+`pendingLandblockRetirements`=131/122 at sawato-baseline/plateau,
+`waitCueShown=true` at holtburg, cpuUs p99 over-limit at the six
+non-Caul stops. The WIP's "exposed pre-existing" classification
+(reasoning in `implementer-progress.md ## Collision-clone`) was made
+BEFORE P1 was discovered — re-judge it against the exception loop.
+
+**P4 — door/use approach regression (in COMMITTED C3c code, `529e0e9d`).**
+Quote: "I dont approach doors when I use them." Using a door no longer
+walks the character to it first. Prime suspect:
+`src/AcDream.App/Input/PlayerModeController.cs`'s conditional MoveTo
+bind (`if (controller.MoveTo is { } moveTo)`) — the legacy path CREATED
+the MoveToManager at attach via factory; the flip only binds approach
+callbacks IF Runtime's publication chain already ran `MakeMoveToManager`
+(`RuntimeLocalPlayerPhysicsPublicationState`). Establish when (or
+whether) Runtime creates it relative to player-mode attach; the
+interaction flow is `SelectionInteractionController` →
+approach-MoveTo → use (see `claude-memory/project_interaction_pipeline.md`
+and register row AD-27).
+
+**P5 — intermittent spell particle loss (#279, C3c-era).**
+One-shot VFX/scripts arriving while their entity is in C3c's
+suppressed-until-receipt window are dropped instead of deferred; retail
+queues scripts for not-yet-in-world objects (grep
+`docs/research/named-retail/acclient_2013_pseudo_c.txt` for the
+PlayScript/pending-script handling around `HandleCreateObject`
+0x00454C80 / `set_hidden` 0x00514C60). Route the deferral through the
+presentation-binding moment
+(`TryApplyInitialCreateCompletionPresentation` in
+`src/AcDream.App/World/LiveEntityRuntime.cs` and the equivalent headless
+sink).
+
+**P6 — verify after P1–P3 land:** purple materialization haze re-firing
+while standing still (#278a — believed the same root as the visibility
+edges), the monster pop-in re-check, slope-glide vs open #269.
+
+## Required process per fix
+
+1. Root cause with file:line evidence BEFORE writing the fix; for any
+   AC-specific behavior, cite the named-retail decomp.
+2. Tests that fail pre-fix and pass post-fix.
+3. Any new retail deviation gets its register row
+   (`docs/architecture/retail-divergence-register.md`) in the SAME
+   commit; when the collision work lands for real, APPLY the prepared
+   `docs-drafts.md` entries (AD-6 successor note, AD-62, digest entries,
+   #280) rather than re-deriving them.
+4. Gates before each commit: `dotnet build AcDream.slnx -c Release`;
+   `dotnet test AcDream.slnx -c Release --no-build --no-restore -m:1`
+   with `ACDREAM_PAK_PATH=C:\Users\erikn\Documents\Asheron's Call\acdream.pak`
+   (baseline: 10,812 passed / 0 failed / 4 skipped);
+   `tools/run-connected-world-lifecycle-gate.ps1` must PASS; then
+   `tools/run-connected-r6-soak.ps1` — the FINAL acceptance:
+   `report.json` `Passed=true`, zero failures, `waitCueShown=false` at
+   all nine stops, per-checkpoint cpuUs p99 within +10% of the
+   20260727-004942 baseline. READ `report.json`, never the markers log.
+   A failure whose only signature is `activeTeleportCount=1` at a stable
+   checkpoint is user interference — one clean re-run allowed; any other
+   failure is real: fix it, don't re-run past it.
+5. COMMIT each completed fix as its own bisectable commit on
+   `codex/port-claude-agents` with a message explaining the why.
+6. Manual verification launch (for the user): the PowerShell launch in
+   CLAUDE.md "Running the client against the live server", plus
+   `ACDREAM_RETAIL_UI=1`.
+
+## Final deliverable
+
+Per-problem disposition (root cause → fix → evidence), the commit SHAs,
+full gate numbers including the soak report values, and an explicit list
+of anything left open.