Request: Add Support for Starting Camera Recording via SDI

[RobinS02]

I’m currently using PyATEMMax to control my ATEM switcher and connected Blackmagic cameras. While the library supports various camera controls (e.g., iris, focus, white balance), I could not find a way to start or stop recording directly on a connected Blackmagic camera (e.g., URSA Mini Pro or Pocket Cinema Camera 4K/6K).

This functionality is crucial for workflows where cameras are remotely operated, and recording needs to be triggered over SDI via the ATEM switcher. Blackmagic cameras support this feature when connected via SDI and controlled using the Blackmagic ATEM SDK.