fix: decouple stuck detector timeout

packages/core/src/__tests__/settings-parity.test.ts

@@ -69,6 +69,11 @@ describe("settings key parity", () => {
     expect(DEFAULT_PROJECT_SETTINGS.completionDocumentationMode).toBe("off");
   });
 
+  it("keeps task stuck timeout active by default without coupling to workflow step timeout", () => {
+    expect(DEFAULT_PROJECT_SETTINGS.taskStuckTimeoutMs).toBe(600_000);
+    expect(DEFAULT_PROJECT_SETTINGS.workflowStepTimeoutMs).toBe(360_000);
+  });
+
   it("keeps github tracking keys in expected scopes with documented defaults", () => {
     expect(DEFAULT_PROJECT_SETTINGS.githubTrackingEnabledByDefault).toBe(false);
     expect(DEFAULT_PROJECT_SETTINGS.githubTrackingDefaultRepo).toBeUndefined();

packages/core/src/settings-schema.ts

@@ -214,7 +214,7 @@ export const DEFAULT_PROJECT_SETTINGS = {
   requirePlanApproval: false,
   specStalenessEnabled: false,
   specStalenessMaxAgeMs: 6 * 60 * 60 * 1000,
-  taskStuckTimeoutMs: undefined,
+  taskStuckTimeoutMs: 600_000,
   aiSessionTtlMs: 7 * 24 * 60 * 60 * 1000,
   aiSessionCleanupIntervalMs: 60 * 60 * 1000,
   autoUnpauseEnabled: true,

packages/core/src/types.ts

@@ -2180,7 +2180,7 @@ export interface ProjectSettings {
   /** Timeout in milliseconds for detecting stuck tasks. When a task's agent session
    *  shows no activity (no text deltas, tool calls, or progress updates) for longer
    *  than this duration, the task is considered stuck and will be terminated and retried.
-   *  Default: undefined (disabled). Suggested value: 600000 (10 minutes). */
+   *  Default: 600000 (10 minutes). Set to 0 to disable. */
   taskStuckTimeoutMs?: number;
   /** TTL in milliseconds for persisted AI planning/subtask/mission interview sessions.
    *  Sessions older than this cutoff are expired by the dashboard session cleanup loop.