Ryan Malloy
e7e71c47d7
Stop handler now calls cancel_operation() on the device bridge, which sets a threading.Event that interrupts the 2s-timeout serial read loop in send_with_timeout(). InterruptedError is caught separately to prevent falling back to software sweep on cancel. disconnect() uses acquire(timeout=5) with force-close fallback instead of blocking lock acquisition — prevents deadlock when a stuck worker holds the serial lock during shutdown. Add 3 Textual async tests (pytest-asyncio) to verify Stop behavior: firmware sweep stop, software sweep stop, and sweep restart.