fix(FN-3175): reduce dashboard log stalls

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

@@ -57,7 +57,7 @@ describe("Database", () => {
       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(autoCheckpoint.wal_autocheckpoint).toBe(1000);
       expect(journalSizeLimit.journal_size_limit).toBe(4_194_304);
     });
 
@@ -267,6 +267,13 @@ describe("Database", () => {
       expect(typeof result.log).toBe("number");
       expect(typeof result.checkpointed).toBe("number");
     });
+
+    it("supports explicit truncate checkpoints when requested", () => {
+      const result = db.walCheckpoint("TRUNCATE");
+      expect(result).toHaveProperty("busy");
+      expect(result).toHaveProperty("log");
+      expect(result).toHaveProperty("checkpointed");
+    });
   });
 
   describe("transactions", () => {

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

@@ -4158,6 +4158,25 @@ Task with acceptance criteria
       expect(events[1]).toMatchObject({ text: "tool", type: "tool", detail: "read file", agent: "executor" });
     });
 
+    it("truncates oversized tool detail before persisting and emitting", async () => {
+      const task = await createTestTask();
+      const events: any[] = [];
+      const oversizedDetail = "X".repeat(5000);
+      const truncationMarker = "[tool output truncated to keep dashboard log views responsive]";
+      store.on("agent:log", (entry) => events.push(entry));
+
+      await store.appendAgentLogBatch([
+        { taskId: task.id, text: "Bash", type: "tool_result", detail: oversizedDetail, agent: "executor" },
+      ]);
+
+      const logs = await store.getAgentLogs(task.id);
+      expect(logs).toHaveLength(1);
+      expect(logs[0].detail).toContain(truncationMarker);
+      expect(logs[0].detail!.match(/\[tool output truncated to keep dashboard log views responsive\]/g)).toHaveLength(1);
+      expect(logs[0].detail!.length).toBeLessThan(oversizedDetail.length);
+      expect(events[0].detail).toBe(logs[0].detail);
+    });
+
     it("appendAgentLogBatch with empty entries is a no-op", async () => {
       const task = await createTestTask();
 
@@ -4304,6 +4323,28 @@ Task with acceptance criteria
       expect(logs[0].detail!.length).toBe(longDetail.length);
     });
 
+    it("clips oversized historical tool detail at read time", async () => {
+      const task = await createTestTask();
+      const oversizedDetail = "Y".repeat(7000);
+      const truncationMarker = "[tool output truncated to keep dashboard log views responsive]";
+
+      insertLogEntryWithTimestamp(
+        store,
+        task.id,
+        "Bash",
+        "tool_result",
+        "2026-04-24T12:00:00.000Z",
+        oversizedDetail,
+        "executor",
+      );
+
+      const logs = await store.getAgentLogs(task.id);
+      expect(logs).toHaveLength(1);
+      expect(logs[0].detail).toContain(truncationMarker);
+      expect(logs[0].detail!.match(/\[tool output truncated to keep dashboard log views responsive\]/g)).toHaveLength(1);
+      expect(logs[0].detail!.length).toBeLessThan(oversizedDetail.length);
+    });
+
     it("appendAgentLog persists and reads back the agent field", async () => {
       const task = await createTestTask();