feat(companion): add heartbeat failure-threshold controls

src/companion/heartbeatLoop.test.ts

@@ -100,4 +100,34 @@ describe('CompanionHeartbeatLoop', () => {
     expect(publishHeartbeat).toHaveBeenCalledTimes(1);
     expect(loop.running).toBe(false);
   });
+
+  it('stops when maxConsecutiveFailures threshold is reached', async () => {
+    const publishHeartbeat = vi
+      .fn<() => Promise<NodeStatusSetResult>>()
+      .mockRejectedValue(new Error('persistent-failure'));
+    const onError = vi.fn();
+    const onFailureLimitReached = vi.fn();
+    const loop = new CompanionHeartbeatLoop(
+      { publishHeartbeat },
+      {
+        intervalMs: 300,
+        onError,
+        maxConsecutiveFailures: 2,
+        onFailureLimitReached,
+      },
+    );
+
+    loop.start();
+    await Promise.resolve();
+    expect(loop.running).toBe(true);
+
+    await vi.advanceTimersByTimeAsync(300);
+    expect(loop.running).toBe(false);
+    expect(onError).toHaveBeenCalledTimes(2);
+    expect(onFailureLimitReached).toHaveBeenCalledTimes(1);
+    expect(onFailureLimitReached).toHaveBeenCalledWith(expect.any(Error), 2);
+
+    await vi.advanceTimersByTimeAsync(1000);
+    expect(publishHeartbeat).toHaveBeenCalledTimes(2);
+  });
 });