pub trait ModifyTrackedFiles {
// Required methods
fn update_tracked_files(&self) -> VersionResult<()>;
fn add_tracked_file(&mut self, file: TrackedFiles) -> VersionResult<()>;
fn remove_tracked_file(&mut self, file: PathBuf) -> VersionResult<()>;
fn update_file(&self, file: PathBuf) -> VersionResult<()>;
fn list_tracked_files(&self) -> VersionResult<Vec<TrackedFiles>>;
// Provided method
fn sync_files(&self) -> VersionResult<()> { ... }
}