test(ha-commit-durability): verify zero acked-job loss + cluster availability across failover on no-self-exit build (task 5.2)

.kiro/specs/ha-commit-durability/tasks.md

@@ -112,7 +112,7 @@
   - _Requirements: 1.1, 1.4, 1.5, 1.6, 2.5_
   - _Depends: 2.2, 4.2_
 
-- [ ] 5.2 Prove zero acknowledged-job loss across failover
+- [x] 5.2 Prove zero acknowledged-job loss across failover
   - Run the deterministic durability E2E and the rolling SIGKILL+restart soak; both must show every acknowledged job surviving every failover.
   - Observable: the deterministic mode that was RED in 1.3 now passes (GREEN), and the soak reports zero DATA LOSS across rounds.
   - _Requirements: 1.1, 1.5, 2.2, 2.3, 2.6_
@@ -144,3 +144,4 @@
 - 5.1: INTEGRATION verification — the end-to-end durable-majority path was ALREADY wired by 2.1/2.2/2.4/4.x (no production gap found); 5.1 adds 3 integration tests + a tiny `#ifdef XCE_TESTING` liveness-observability seam (`persist_test_last_fdatasync_thread`, nm-excluded from prod). `test_durable_majority_commit_end_to_end`: holds durability off (forced fsync-fail), delivers BOTH standby ACKs, asserts committed_lsn/WAIT do NOT release (ACK-majority alone insufficient) — then flush makes self durable ⇒ committed advances + WAIT releases rc=0; asserts `committed_lsn <= durable_lsn`. RED proof: injecting the pre-2.2 `highest_appended_lsn` cap trips `assert(cand <= persist_durable_lsn)`. `test_sole_durable_contributor_loss_survives` (Req 1.5/2.5): property-asserted (committed ⇒ ≥⌊N/2⌋+1 durable copies, two persist dirs, drop one) — LIVE failover proof is 5.2. `test_durability_work_off_iomgr_preserves_liveness` (Req 1.6): seam records the flusher thread id; asserts fdatasync runs off the caller/iomgr thread + heartbeat reads stay <50ms during flushes. GOTCHA: a real persist with registered standbys needs the `XCE_TESTING repl_broadcast_send_hook` (drop) installed before append, else dummy endpoints trip an ASAN overflow in `dataq_enq`. CAVEATS (for 5.3/validation): (1) meson `Fail:0` masks Unity sub-group failures — gate on `grep -c :FAIL: testlog.txt`==0; (2) run on a fsync-able fs (the pre-existing test_fact_hook_append EIO failure is /tmp-overlay-only). 4.3 catch-up-timer-before-FATAL still a follow-up. Reviewed in MAIN CONTEXT (subagent spend limit).
 - 4.4: Closed the 5.2-soak liveness gap. `raft_cb_become_leader` NO LONGER FATALs synchronously — on FENCE / would-be-FATAL (truncated or durable_floor < HWM) it calls `ha_arm_promotion_fence_timer` (sets `in_catch_up`, schedules a one-shot `delay_task_ms(&c->delaymgr, ha_promotion_fence_window_ms(), 1, promotion_fence_timeout_fn, ctx)`) and RETURNS without becoming primary. The timer callback (`promotion_fence_timeout_fn`, ha.c:702) re-reads LIVE state after the window: caught-up (`!truncated && durable_floor>=HWM`) → release fence, NO FATAL (Req 2.6); peer reachable (`repl_active_standby_count>0`) OR durable_floor advanced past the arm-time baseline → progress possible, leave fenced (existing catch-up machinery / next promotion-gate ELIGIBLE releases it), NO FATAL; ONLY still-truncated/behind + no-peer + no-progress → 3.3 `persist_recover_fatal_if_unrecoverable` (Req 2.4). UAF-safe cancel (`ha_cancel_promotion_fence_timer`: cancelled flag + atomic-exchange the stored ctx; handle cleared before the cancelled-check, mirrors `raft_election_timeout_fn`); cancelled in `ha_fini`; fail-loud if `delay_task_ms` itself fails (never fence indefinitely). Test window seam `ha_set_promotion_fence_window_ms` + driver `ha_arm_promotion_fence_timer_for_test`. 3 tests (defers-fatal-to-timer, released-on-catchup-no-fatal, cancel-prevents-fatal) with RED proof (re-injecting sync FATAL → 3 fails). Reviewed MAIN CONTEXT (subagent spend limit): suite :FAIL:==0, /tmp fsync-able this run. NOTE: this is the bounded-window timer 4.3/5.1 deferred; with it, 5.2's soak should keep the cluster available (truncated rejoiners catch up, not die).
 - REWORK (2026-06-18, user invariant — a controller MUST NEVER self-terminate): tasks 3.3/4.3/4.4 had implemented Req 2.4 "fail loud" as a SELF-ABORT (`persist_recover_fatal_if_unrecoverable → tlog_exit(); abort()` + `persist_fatal_hook`). That violated the invariant (a self-exited controller needs MANUAL admin recovery + leaves quorum degraded; a live retrying node self-heals when a peer returns) and was the true root cause of the 5.2 soak quorum collapse. CORRECTED: removed the abort/exit terminal entirely. New: `persist_recover_loud_fence_if_unrecoverable(persist_t*)` (NO abort) logs a loud operator-visible ERROR (truncation boundary vs cluster HWM) + sets sticky `_Atomic bool recovery_unrecoverable` (accessors `persist_recovery_unrecoverable`/`persist_clear_recovery_unrecoverable`); the member STAYS ALIVE, permanently non-promotable/fenced (`in_catch_up` + the sticky flag both consulted by the promotion gate), and KEEPS RETRYING catch-up. Decision enum `RECOVER_DECISION_FATAL` → `RECOVER_DECISION_FENCE_UNRECOVERABLE` (non-terminating). 4.4 timer no longer aborts — it re-emits the loud operator alert + re-arms (operator visibility), never exits. Flag + fence CLEAR automatically on catch-up (not truncated AND durable_floor ≥ HWM) → re-eligible (Req 2.6), fully automatic. `persist_fatal_hook` removed. Verified: grep/nm show NO abort/exit/tlog_exit on the recovery path; ASAN suite :FAIL:==0; reworked tests (row4/4b → loud_fence, unrecoverable-stays-alive-loud, released-on-catchup, cancel-stops-realert) PASS. Spec updated: requirements.md Req 2.4 + design.md (decision table rows 4/4b, RecoveryIntegrity, traceability, FATAL-vs-fence open question) reworded "FATAL/terminate" → "LOUD PERMANENT FENCE (non-promotable, stays alive, keeps retrying — NEVER self-exit)". PROJECT-WIDE GUIDANCE added: `src/controller/CLAUDE.md` §"Process Lifecycle (DESIGN INVARIANT)" + `.kiro/steering/ha-async-io.md` — controllers never self-terminate. (`ha_self_restart` execv-restart in convergence/demotion is a SEPARATE primitive, untouched.)
+- 5.2: PASS on the reworked (no-self-exit) build. (a) DETERMINISTIC E2E flipped RED→GREEN, stable 3/3 runs / 9-9 probes — in-window primary fdatasync ≥1 (=2) precedes the ack ("durable-before-ack"), the inverse of 1.3's unfixed RED. (b) ROLLING SIGKILL soak (6 rounds) exit 0 = ZERO acknowledged-job loss, cluster stayed continuously available, 0 self-terminations (the no-self-exit rework removed the abort that collapsed quorum in the first attempt). Validation-only (no production code). NOTE: ran in-sandbox via background+poll on a worktree deploy dir (avoids /tmp overlay EIO); the earlier collapse was the abort terminal, now corrected — a host re-run is still good practice but the in-sandbox soak now passes with the fix.