Root cause (measured live via ACDREAM_PROBE_PARK=1): HeadlessSessionWorldProjection
drove the first-entry conductor unconditionally, including while
HeadlessCollisionNeighborhood's own 3x3 publication plan held a genuinely open
RuntimeCollisionAdmission for the local player's landblock. Every
TrySealCollisionEvaluationAuthority attempt during that window failed
(IsCollisionEvaluationPrefixAdmissible false) and retried forever without
recovering — measured verdict: "seal-refused" repeating with no preceding
[rearm] verdict= line (the operation never even reached the AwaitingCell park).
This is the diagnosis doc's "structural half" mechanism; no evidence of the
"circular HasOldPrefixPlacementDebt" hypothesis was observed, so that shape
was not needed.
Step 1 (enabler): HeadlessStaticStateAudit.ValidateProcessIsolation now takes
sessionCount and only refuses process-global physics probes for
sessionCount > 1 — its own multi-root-attribution rationale never applied to
a single session, and it was blocking the exact probe built to diagnose this
class of stall.
Step 3a (root cause): new IHeadlessCollisionNeighborhood.IsQuiescent gates
ProjectSpawn/ProjectPosition/PumpFirstEntry's conductor-drive calls — the
conductor is never driven while the neighborhood's own publication owns
collision authority for that tick.
Step 4 (defense-in-depth): HeadlessLocalPlayerFrameHost.CanAdvancePlayer now
requires Controller.CanExecuteLiveMovement instead of just a non-null
controller — the headless-only gap that turned the (now-fixed) hydration
stall into a hard crash reaching SuspendObjectUpdate on a dormant controller.
RuntimeLocalPlayerFrameController's three shared entry points gained the same
guard, contract-preserving for the graphical host.
Verified end-to-end against live ACE (jump-probe policy, three runs):
hydration succeeds cleanly (136 entities load vs. 0 before), no seal-refused
spam, no crash from the original bug, graceful logout every time. Full
airborne-transition confirmation is blocked by a separate, newly-discovered,
pre-existing defect filed as #368 (the headless scheduler's
Task.Delay(...).ConfigureAwait(false) tick loop can resume on a different
ThreadPool thread mid collision-generation, tripping
EnsureCollisionMutationThread) — explicitly out of scope here, not mentioned
anywhere in the #365 diagnosis, and unsafe to fix without graphical-host
verification this session was constrained not to perform.
New tests: the real-admission hydration test (fails on the pre-Step-3a tree,
verified by temporarily reverting the three gates and confirming failure,
then restoring), the PumpFirstEntry quiescence-gate test, the
CanAdvancePlayer publication-lifecycle test, the dormant-controller
sabotage tests for RuntimeLocalPlayerFrameController, and the audit
single/multi-session tests. RuntimeLocalPlayerPhysicsPublicationStateTests
is untouched.
Full Release suite: 12,343 passed / 4 skipped / 0 failed (baseline ~12,330/4
plus 11 new tests).
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
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