feat: Enhance sample selection handling in SequencerTrack component

Commit notes

This commit updates the handleSampleSelect function to improve track loading management when a new sample is selected. It now stores the old track ID for cleanup purposes and ensures that audio data from the previous track is cleared if necessary. Additionally, the updateTrackSample function is modified to return the old track, allowing for better audio data management during transitions. These changes enhance the overall functionality and user experience of the sequencer.