perf(queue): prepare the transition wake lookup once per repository (#2013)

Queue history reads call the wake lookup once per transition. Preparing the same indexed statement for each call added avoidable work to health-diagnosis reads with long histories. Prepare it lazily once per repository instance and keep every lookup fresh; no query results are cached. Availability, ordering, misses and errors retain their behavior.

Validation: 140 affected tests and daemon typecheck pass. Independent Codex and Claude source reviews passed on the identical two-file change. A real-database test checks a warmed miss, insertion, update and deletion.

In one synthetic daemon replay with 100 owned diagnoses and 6,900 history transitions, reference/candidate/candidate/reference evaluation means were 918/759/745/1,014 ms: combined 966 → 752 ms. All 12 evaluations retained complete coverage and all 16 native-consumer checks passed. Reference drift was 96 ms and individual ranges overlapped. This is a local improvement on that workload; the recurring severe-stall cause remains unresolved.

packages/daemon/src/domain/queue-wake-repository.ts

@@ -56,6 +56,9 @@ interface WakeRow {
 /** Persistence + live-state projection for transition-bound park wakes. */
 export class QueueWakeRepository {
   private readonly available: boolean;
+  /** One lookup statement for this connection, prepared on first use: history reads call it once per transition, and
+   *  compiling it each time dominated their cost. It holds no result; every call reads afresh. */
+  private lookup: Database.Statement | undefined;
 
   constructor(private readonly db: Database.Database) {
     this.available = this.db.prepare(
@@ -81,9 +84,8 @@ export class QueueWakeRepository {
 
   getForTransition(transitionId: number): QueueWakeRecord | null {
     if (!this.available) return null;
-    const row = this.db.prepare(
-      "SELECT * FROM queue_transition_wakes WHERE transition_id = ?",
-    ).get(transitionId) as WakeRow | undefined;
+    this.lookup ??= this.db.prepare("SELECT * FROM queue_transition_wakes WHERE transition_id = ?");
+    const row = this.lookup.get(transitionId) as WakeRow | undefined;
     return row ? this.row(row) : null;
   }
 

packages/daemon/test/queue-park-wake.test.ts

@@ -1452,3 +1452,26 @@ describe("S03 R25 — a park records its wake on the append-only transition", ()
     });
   });
 });
+
+describe("wake lookup reads afresh on every call", () => {
+  it("a warmed miss, then a recorded wake, then an update are each seen by the next lookup", async () => {
+    const { ALL_MIGRATIONS } = await import("../src/db/all-migrations.js");
+    const { QueueWakeRepository } = await import("../src/domain/queue-wake-repository.js");
+    const db = createDb();
+    try {
+      migrate(db, ALL_MIGRATIONS);
+      db.exec("INSERT INTO queue_items (qitem_id, ts_created, ts_updated, source_session, destination_session, state, priority, body) VALUES ('q1', '2026-01-01T00:00:00Z', '2026-01-01T00:00:00Z', 'a@r', 'b@r', 'blocked', 'routine', 'x')");
+      const transitionId = Number(db.prepare("INSERT INTO queue_transitions (qitem_id, ts, state, actor_session) VALUES ('q1', '2026-01-01T00:00:00Z', 'blocked', 'b@r')").run().lastInsertRowid);
+      const wakes = new QueueWakeRepository(db);
+      // Warm the lookup with a miss, and an unknown id.
+      expect(wakes.getForTransition(transitionId)).toBeNull();
+      expect(wakes.getForTransition(transitionId + 999)).toBeNull();
+      wakes.record({ transitionId, qitemId: "q1", phase: "armed", kind: "timer", ref: "30s", deliveryStatus: null });
+      expect(wakes.getForTransition(transitionId)).toMatchObject({ transitionId, qitemId: "q1", phase: "armed", kind: "timer", ref: "30s", deliveryStatus: null });
+      db.prepare("UPDATE queue_transition_wakes SET delivery_status = 'delivered' WHERE transition_id = ?").run(transitionId);
+      expect(wakes.getForTransition(transitionId)?.deliveryStatus).toBe("delivered");
+      db.prepare("DELETE FROM queue_transition_wakes WHERE transition_id = ?").run(transitionId);
+      expect(wakes.getForTransition(transitionId)).toBeNull();
+    } finally { db.close(); }
+  });
+});