feat(gateway): wire safe-point runtime cancellation for agent.cancel

src/gateway/session-bridge.test.ts

@@ -113,6 +113,24 @@ describe('SessionBridge', () => {
     expect(bridge.isBusy('conn-1')).toBe(false);
   });
 
+  it('cancel returns false when no active operation exists', () => {
+    const bridge = createBridge();
+    bridge.connect('conn-1');
+
+    expect(bridge.cancel('conn-1')).toBe(false);
+  });
+
+  it('cancel requests cancellation when connection is busy', () => {
+    const bridge = createBridge();
+    bridge.connect('conn-1');
+    const agent = bridge.getAgent('conn-1');
+    const cancelSpy = vi.spyOn(agent!, 'cancel');
+
+    bridge.setBusy('conn-1', true);
+    expect(bridge.cancel('conn-1')).toBe(true);
+    expect(cancelSpy).toHaveBeenCalledTimes(1);
+  });
+
   it('switchSession changes session for a connection', () => {
     const bridge = createBridge();
     bridge.connect('conn-1');