v0.5.13

Fixes from the 2026-07-12 focused re-audit of the v0.5.12 delta. Headline: the v0.5.12 H-1 fix was a no-op in production and is now actually closed.

Fixed

• Submit depends_on TOCTOU fix was a no-op (H-1, regression of the v0.5.12 fix). The v0.5.12 post-commit cascade re-check read the parent through a cached identity-map object; with expire_on_commit=False the intervening commit never refreshed it, so the cascade gate saw a stale non-terminal state and never fired — a child concurrently orphaned by its parent still stranded QUEUED forever. /submit now session.refresh()es each parent before the cascade re-check (matching the idiom every other _cascade_on_parent_terminal caller already uses), guarded for a parent pruned mid-submit. New real-race regression test drives the actual /submit endpoint with a concurrent-session /complete and fails on the pre-fix code.
• scheduling_timeout queue-clock reset on refuse-admission re-routes (M-1 follow-up). A refuse-admission requeue funnels through the same helper that resets last_enqueued_at, so a job that never ran but kept getting offered-and-refused (e.g. oscillating gpu_contention, which does not grow the exclusion set) reset its timeout clock every bounce and could evade scheduling_timeout forever. Refuse-admission re-routes now preserve the clock; only requeues of a job that actually dispatched reset it.
• Worker run_job exception path leaked a signal-poll thread and a fast_path child (F1/F2). On a raise past the terminal path, the outer finally now stops the signal-poll thread (it would otherwise spin on GET /signal forever for a terminal job) and SIGKILLs a fast_path child that has no scope cgroup to reap.

CI

• Property-based fuzzing of the broker state machine (H-4, audit 2026-07-10). A hypothesis RuleBasedStateMachine (tests/property/) generates arbitrary interleavings of submit / claim / start / complete / cancel / worker-death-reclaim / scheduling-timeout / sweep against the real broker (in-process FastAPI + SQLite + sweeper) and asserts the invariants the CAS discipline guarantees: no terminal state is ever clobbered, a job is terminally cancelled at most once, a reclaim never silently drops a pending user cancel, and (added 2026-07-12) a default-policy dependent of a failed parent is never stranded on a runnable path. The harness now generates depends_on edges so it actually exercises the cascade (previously it created none, leaving the cancel-at-most-once invariant vacuous). Runs bounded in CI (JOBD_H4_EXAMPLES / JOBD_H4_STEPS env overrides for a deep run).
• The live CI job silently skipped 5 of 9 marked-live tests (H-3 follow-up). It exported only JOBD_LIVE, while the e2e / MCP / project-defaults live tests gate on JOBD_E2E / RUN_LIVE_JOBD and require an external broker — so they skipped, and skips don't fail pytest. The job now stands up a real broker + worker from the committed config/, exports all three opt-in gates, and guards against a broken gate silently running zero tests.