fix: model replay review cancellation

web/apps/console/src/demo/timeline/reducer.test.ts

@@ -109,4 +109,20 @@ describe("demoTimelineReducer", () => {
     expect(restarted.mode).toBe("replay");
     expect(restarted.appliedCount).toBe(0);
   });
+
+  it("cancels review as a terminal non-autoplay phase", () => {
+    const reviewing = {
+      ...initialDemoTimelineState,
+      mode: "replay" as const,
+      phase: "review" as const,
+      events: [event(0, "interrupt")],
+      appliedCount: 1,
+      autoplay: false,
+    };
+    const cancelled = demoTimelineReducer(reviewing, { type: "cancel_review" });
+
+    expect(cancelled.phase).toBe("cancelled");
+    expect(cancelled.autoplay).toBe(false);
+    expect(cancelled.appliedCount).toBe(1);
+  });
 });

web/apps/console/src/demo/timeline/reducer.ts

@@ -6,6 +6,7 @@ export type DemoTimelinePhase =
   | "running"
   | "paused"
   | "review"
+  | "cancelled"
   | "completed"
   | "failed";
 
@@ -35,6 +36,7 @@ export type DemoTimelineAction =
   | { readonly type: "pause" }
   | { readonly type: "play" }
   | { readonly type: "continue_review" }
+  | { readonly type: "cancel_review" }
   | { readonly type: "fail"; readonly message: string; readonly event?: DemoEvent }
   | { readonly type: "restart" }
   | {
@@ -102,6 +104,10 @@ export const demoTimelineReducer = (
       return state.phase === "review"
         ? { ...state, phase: "running", autoplay: true }
         : state;
+    case "cancel_review":
+      return state.phase === "review"
+        ? { ...state, phase: "cancelled", autoplay: false }
+        : state;
     case "fail":
       return {
         ...state,

web/apps/console/src/demo/useDemoTimeline.test.tsx

@@ -395,6 +395,23 @@ describe("useDemoTimeline", () => {
     expect(result.current.trace?.frames.length).toBeGreaterThan(0);
   });
 
+  it("replay cancellation stops without consuming submitted branch", async () => {
+    vi.useFakeTimers();
+    const { result } = renderHook(() => useDemoTimeline(null, vi.fn()));
+    act(() => result.current.setMode("replay"));
+    act(() => result.current.start());
+    for (let i = 0; i < 3; i++) {
+      await act(async () => vi.advanceTimersByTimeAsync(900));
+    }
+
+    await act(async () => result.current.cancelReview("Cancelled."));
+    await act(async () => vi.advanceTimersByTimeAsync(1800));
+
+    expect(result.current.state.phase).toBe("cancelled");
+    expect(result.current.state.events[result.current.state.appliedCount - 1]?.stage).toBe("interrupt");
+    expect(result.current.output).toBeNull();
+  });
+
   it("missingDeploymentMessage shows when live mode with null target", () => {
     const { result } = renderHook(() => useDemoTimeline(null, vi.fn()));
     expect(result.current.missingDeploymentMessage).toContain("Not connected");

web/apps/console/src/demo/useDemoTimeline.ts

@@ -292,8 +292,8 @@ export const useDemoTimeline = (
       comment,
       outcome: "cancelled",
     };
-    dispatch({ type: "continue_review" });
-  }, []);
+    dispatch({ type: state.mode === "live" ? "continue_review" : "cancel_review" });
+  }, [state.mode]);
 
   const restart = useCallback(() => {
     resetRuntime();