PR #27 scoped the lock-free parked-checkpoint answer to exact checkpoint
task/session equality. Company gate cards are raised by role work-item
tasks but answered from the run's anchor chat, whose task id only
appears in payload["task_ids"] — the exact-match guard silently
disabled the fast path for precisely the answers it exists for and
re-opened the project-0012 late-approval lock wedge. Scope by the same
linkage set _find_parked_checkpoint_for_deferred_resume uses (checkpoint
task/session plus payload waiting_task_id/task_ids), keep rejecting
unrelated channels, and keep legacy checkpoints without linkage
deliverable.
The new fail-closed identity errors in _process_session_message raised
out of fire-and-forget background tasks (_track_session), where they are
only logged and the user's message silently vanishes. Surface them as a
visible system chat error and stop instead of raising.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
LZH-YS1998
57610e57a6