feat(election-iomgr-refactor): COMMITTING path in ha_elect_evaluate_and_signal + committing/election timeout watchdogs — tasks 4.1, 4.3, 4.4

src/controller/ha.h

@@ -96,6 +96,10 @@ typedef struct {
      * (quorum-reached path) can set timeout_ctx->cancelled = 1 to cancel the
      * watchdog.  Set by ha_start_election_async after scheduling the timeout. */
     void            *timeout_ctx;      /* election_timeout_ctx_t*; NULL until watchdog scheduled */
+    /* Task 4.1: cluster_t* so ha_elect_evaluate_and_signal can call
+     * cluster_init_phase2(c) and arm the committing timeout watchdog.
+     * NULL in unit tests (c=NULL bypasses phase2 and watchdog arming). */
+    cluster_t       *c;
     ha_vote_entry_t  votes[];          /* C99 flexible array: n_peers-1 entries */
 } ha_elect_ctx_t;
 
@@ -496,9 +500,24 @@ int ha_find_and_connect_to_primary(ha_state_t *ha,
 #define HA_FIND_PRIMARY_T3_INIT_MS     100
 #define HA_FIND_PRIMARY_T3_MAX_MS     5000
 
+/*
+ * ha_repl_ack_received: called when a standby ACKs config+WAL catch-up
+ * (OPCode_replCatchUpDone).  Increments repl_ack_count; when majority
+ * threshold is reached, calls ha_promote_to_primary (Req 8.2).
+ */
+void ha_repl_ack_received(ha_state_t *ha, cluster_t *c);
+
 /* ── P3-6: Test-only failover shim ────────────────────────────── */
 
 #ifdef XCE_TESTING
+/*
+ * ha_phase2_hook: test-only seam for cluster_init_phase2.
+ * When non-NULL, ha_elect_evaluate_and_signal() calls this INSTEAD OF the
+ * real cluster_init_phase2() so unit tests can count phase2 calls without
+ * requiring a real cluster_t.  Pattern mirrors xce_vote_request_hook.
+ */
+extern int (*ha_phase2_hook)(void *c);
+
 /* Test-only shim: demote then re-promote; returns new term.
  * Exercises the manual failover state machine without a live cluster_t.
  * Calls ha_do_demote() then ha_do_promote(); validates role transitions