python: Better error checking for events from python

[rm5248]

Use a context manager when locking in python to ensure that if an exception is thrown, the lock will be released.

Add some basic error checking to the submit_event function to make sure that card read events have the correct data set.

fixes: #267

[Copilot]

Pull request overview

This PR improves error handling and thread safety in the Python OSDP peripheral device implementation. The changes use context managers for lock management to ensure locks are released even when exceptions occur, and add validation for card read events to catch malformed event data early.

Key changes:

• Replaced manual lock.acquire()/lock.release() calls with context manager pattern (with lock:) for exception safety
• Added input validation to submit_event() to verify event structure and required fields for card read events
• Imported Event and CardFormat constants to support the new validation logic

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[sidcha]

@rm5248 Please ignore the AI review, I'm just trying it out.

[sidcha]

These are checked in osdp_sys and the missing keys are reported from there (see here). If this info is insufficient, the code there needs to be extended to avoid code duplication.

[rm5248]

It is checked there, but the problem is that the calling code overwrites the python exception here in pd.c. This leads to the unclear error message.

If you comment out that line in pd.c the proper exception is set.

My logic behind doing it in python is that it's easier to check for multiple keys and give the user a more clear error message before dropping to the C code.