feat(FN-3173): add SQLite WAL tuning, integrity checks, and agent log batch

This merge brings FN-3173's SQLite stability improvements: WAL tuning pragmas for better concurrency, periodic integrity checks with self-healing recovery, and batched agent log writes to reduce I/O overhead. It also includes a new cron-runner for scheduled maintenance tasks, TUI mouse wheel scrolli

Fusion-Task-Id: FN-3173

packages/core/src/__tests__/db.test.ts

@@ -51,6 +51,29 @@ describe("Database", () => {
       expect(row.foreign_keys).toBe(1);
     });
 
+    it("sets WAL tuning pragmas for disk-backed databases", () => {
+      const synchronous = db.prepare("PRAGMA synchronous").get() as { synchronous: number };
+      const autoCheckpoint = db.prepare("PRAGMA wal_autocheckpoint").get() as { wal_autocheckpoint: number };
+      const journalSizeLimit = db.prepare("PRAGMA journal_size_limit").get() as { journal_size_limit: number };
+
+      expect(synchronous.synchronous).toBe(1); // NORMAL
+      expect(autoCheckpoint.wal_autocheckpoint).toBe(100);
+      expect(journalSizeLimit.journal_size_limit).toBe(4_194_304);
+    });
+
+    it("does not force WAL tuning pragmas for in-memory databases", () => {
+      const memDb = new Database(fusionDir, { inMemory: true });
+      memDb.init();
+
+      const autoCheckpoint = memDb.prepare("PRAGMA wal_autocheckpoint").get() as { wal_autocheckpoint: number };
+      const journalSizeLimit = memDb.prepare("PRAGMA journal_size_limit").get() as { journal_size_limit: number };
+
+      expect(autoCheckpoint.wal_autocheckpoint).toBe(1000);
+      expect(journalSizeLimit.journal_size_limit).toBe(-1);
+
+      memDb.close();
+    });
+
     it("creates all expected tables", () => {
       const tables = db.prepare(
         "SELECT name FROM sqlite_master WHERE type='table' ORDER BY name"
@@ -409,6 +432,28 @@ describe("Database", () => {
     });
   });
 
+  describe("integrity check", () => {
+    it("returns ok for healthy databases and leaves corruption flag false", () => {
+      expect(db.corruptionDetected).toBe(false);
+      expect(db.integrityCheck()).toEqual({ ok: true });
+    });
+
+    it("keeps corruptionDetected false after init for healthy database", () => {
+      const diskDb = new Database(fusionDir);
+      diskDb.init();
+      expect(diskDb.corruptionDetected).toBe(false);
+      diskDb.close();
+    });
+
+    it("skips integrity check side effects for in-memory databases", () => {
+      const memDb = new Database(fusionDir, { inMemory: true });
+      memDb.init();
+      expect(memDb.integrityCheck()).toEqual({ ok: true });
+      expect(memDb.corruptionDetected).toBe(false);
+      memDb.close();
+    });
+  });
+
   describe("foreign key cascade across reopen", () => {
     it("cascade delete works after closing and reopening the database", () => {
       const now = new Date().toISOString();

packages/core/src/__tests__/store.test.ts

@@ -4141,6 +4141,31 @@ Task with acceptance criteria
       expect(events[0].taskId).toBe(task.id);
     });
 
+    it("appendAgentLogBatch inserts all entries and emits per-entry events", async () => {
+      const task = await createTestTask();
+      const events: any[] = [];
+      store.on("agent:log", (entry) => events.push(entry));
+
+      await store.appendAgentLogBatch([
+        { taskId: task.id, text: "batch 1", type: "text" },
+        { taskId: task.id, text: "tool", type: "tool", detail: "read file", agent: "executor" },
+      ]);
+
+      const logs = await store.getAgentLogs(task.id);
+      expect(logs).toHaveLength(2);
+      expect(logs.map((entry) => entry.text)).toEqual(["batch 1", "tool"]);
+      expect(events).toHaveLength(2);
+      expect(events[1]).toMatchObject({ text: "tool", type: "tool", detail: "read file", agent: "executor" });
+    });
+
+    it("appendAgentLogBatch with empty entries is a no-op", async () => {
+      const task = await createTestTask();
+
+      await store.appendAgentLogBatch([]);
+
+      expect(await store.getAgentLogCount(task.id)).toBe(0);
+    });
+
     it("appendAgentLog writes detail when provided", async () => {
       const task = await createTestTask();