fix(background-agent): extend default no-progress stale timeout to 30 minutes

Give never-updated background tasks a longer default window and keep the default-threshold regression coverage aligned with that behavior.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

src/features/background-agent/constants.ts

@@ -4,7 +4,7 @@ import type { BackgroundTask, LaunchInput } from "./types"
 export const TASK_TTL_MS = 30 * 60 * 1000
 export const MIN_STABILITY_TIME_MS = 10 * 1000
 export const DEFAULT_STALE_TIMEOUT_MS = 180_000
-export const DEFAULT_MESSAGE_STALENESS_TIMEOUT_MS = 600_000
+export const DEFAULT_MESSAGE_STALENESS_TIMEOUT_MS = 1_800_000
 export const MIN_RUNTIME_BEFORE_STALE_MS = 30_000
 export const MIN_IDLE_TIME_MS = 5000
 export const POLLING_INTERVAL_MS = 3000

src/features/background-agent/default-message-staleness-timeout.test.ts

@@ -0,0 +1,60 @@
+declare const require: (name: string) => any
+const { describe, expect, test, mock } = require("bun:test")
+
+import { DEFAULT_MESSAGE_STALENESS_TIMEOUT_MS } from "./constants"
+import { checkAndInterruptStaleTasks } from "./task-poller"
+import type { BackgroundTask } from "./types"
+
+function createRunningTask(startedAt: Date): BackgroundTask {
+  return {
+    id: "task-1",
+    sessionID: "ses-1",
+    parentSessionID: "parent-ses-1",
+    parentMessageID: "msg-1",
+    description: "test",
+    prompt: "test",
+    agent: "explore",
+    status: "running",
+    startedAt,
+    progress: undefined,
+  }
+}
+
+describe("DEFAULT_MESSAGE_STALENESS_TIMEOUT_MS", () => {
+  test("uses a 30 minute default", () => {
+    // #given
+    const expectedTimeout = 30 * 60 * 1000
+
+    // #when
+    const timeout = DEFAULT_MESSAGE_STALENESS_TIMEOUT_MS
+
+    // #then
+    expect(timeout).toBe(expectedTimeout)
+  })
+
+  test("does not interrupt a never-updated task after 15 minutes when config is omitted", async () => {
+    // #given
+    const task = createRunningTask(new Date(Date.now() - 15 * 60 * 1000))
+    const client = {
+      session: {
+        abort: mock(() => Promise.resolve()),
+      },
+    }
+    const concurrencyManager = {
+      release: mock(() => {}),
+    }
+    const notifyParentSession = mock(() => Promise.resolve())
+
+    // #when
+    await checkAndInterruptStaleTasks({
+      tasks: [task],
+      client: client as never,
+      config: undefined,
+      concurrencyManager: concurrencyManager as never,
+      notifyParentSession,
+    })
+
+    // #then
+    expect(task.status).toBe("running")
+  })
+})

src/features/background-agent/task-poller.test.ts

@@ -117,13 +117,13 @@ describe("checkAndInterruptStaleTasks", () => {
   })
 
   it("should use DEFAULT_MESSAGE_STALENESS_TIMEOUT_MS when messageStalenessTimeoutMs is not configured", async () => {
-    //#given — task started 15 minutes ago, no config for messageStalenessTimeoutMs
+    //#given — task started 35 minutes ago, no config for messageStalenessTimeoutMs
     const task = createRunningTask({
-      startedAt: new Date(Date.now() - 15 * 60 * 1000),
+      startedAt: new Date(Date.now() - 35 * 60 * 1000),
       progress: undefined,
     })
 
-    //#when — default is 10 minutes (600_000ms)
+    //#when — default is 30 minutes (1_800_000ms)
     await checkAndInterruptStaleTasks({
       tasks: [task],
       client: mockClient as never,