FR: Independent Properties for Split Video Segments

User Story: As a video editor, I want to apply properties (e.g., size, position, effects) to individual segments of a split video clip, so I can have more creative control over my final output. Problem: Currently, property changes to one segment of a split clip affect all segments. This limits flexibility in editing and forces workarounds to achieve desired effects. Proposed Solution: Allow properties to be applied independently to each segment of a split video clip. Steps to Reproduce: 1. Start with a video clip containing both a screen recording and a webcam recording. 2. Split the clip into two segments. 3. Select the first segment. 4. In the "Camera Recording" settings, choose "Fullscreen". 5. Observe that both video segments are now in fullscreen mode, instead of just the selected first segment.