This commit includes several improvements and fixes to the visca_over_ip Camera and CachingCamera classes:

- Improved `Camera.__init__` error handling: Re-raises `ViscaException` if clearing the camera's interface socket fails during initialization.
- Refined `Camera.reset_sequence_number`: Ensures client-side sequence number is reset only if a confirmation response is received from the camera.
- Fixed `Camera.get_focus_mode()`: Corrected error handling for unknown or malformed responses, removing an unreachable code path.
- Strengthened `CachingCamera.__init__` resilience: The constructor now handles potential `ViscaException` when fetching the initial focus mode, allowing the object to be created by defaulting `focus_mode` to `None` and printing a warning.
- Added missing docstrings: Provided documentation for several public methods in `camera.py` related to adjusting gain, shutter, iris, brightness, exposure, and aperture.

Potential Issue Noted:
During the addition of docstrings, I observed that the methods `increase_white_balance_temperature`, `decrease_white_balance_temperature`, and `reset_white_balance_temperature` in `camera.py` use VISCA commands identical to those for red gain adjustment. This is likely a bug and requires further investigation to ensure correct camera operation for white balance temperature.