Added:
- Per-set tracking: weight, distance, assistance
- Search in exercise creation screen
- "Add another set" on single-mode result
- Estimated program duration on edit/preview

Improved:
- Sound effects: ToneGenerator to SoundPool
- Unified circular timer font size (80sp)
- Allow 0 as rest interval value
- Hide rest input for single-exercise programs

Fixed:
- Repeating alarm in isometric manual mode
- Exercise order in interval add dialog

Contributors: @lejun (fr), @SomeTr (uk)