Previously, using multiple track selection flags like `-S -A` would not work
as expected. The flags were treated as mutually exclusive, resulting in only
one type of track being downloaded.
This change refactors the track selection logic to properly handle combinations:
- Multiple "only" flags now work together (e.g., `-S -A` downloads both)
- Exclusion flags (`--no-*`) continue to work and override selections
- Default behavior (no flags) remains unchanged
Fixes#10
4dff597af2