feat(FN-5403): merge fusion/fn-5403

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

@@ -166,6 +166,7 @@ describe("settings key parity", () => {
 
   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.runtimeStopDrainMs).toBe(2_000);
     expect(DEFAULT_PROJECT_SETTINGS.workflowStepTimeoutMs).toBe(360_000);
   });
 

packages/core/src/settings-schema.ts

@@ -287,6 +287,7 @@ export const DEFAULT_PROJECT_SETTINGS = {
   specStalenessEnabled: false,
   specStalenessMaxAgeMs: 6 * 60 * 60 * 1000,
   taskStuckTimeoutMs: 600_000,
+  runtimeStopDrainMs: 2_000,
   engineActiveSinceMs: undefined,
   engineActivationGraceMs: 5 * 60_000,
   inReviewStallDeadlockThreshold: 3,

packages/core/src/types.ts

@@ -3084,6 +3084,10 @@ export interface ProjectSettings {
    *  than this duration, the task is considered stuck and will be terminated and retried.
    *  Default: 600000 (10 minutes). Set to 0 to disable. */
   taskStuckTimeoutMs?: number;
+  /** Maximum milliseconds InProcessRuntime.stop() waits for in-flight tasks to drain
+   *  AFTER aborting their AI sessions. Default: 2000. Set to 0 to skip drain waits
+   *  entirely (test/CI). Set to 30000 to preserve the historical 30s grace window. */
+  runtimeStopDrainMs?: number;
   /** Epoch ms when the in-process runtime last became active (startup or transition
    *  out of globalPause/enginePaused). Time-based stuck/stalled/stale detectors floor
    *  their activity anchor at this value so engine downtime is not counted as quiet time.