Add proper audio file handling for timers and alarms
With the upcoming Plasma Mobile sound contest (https://phabricator.kde.org/T14204), we will have a bunch of default sounds to work with. We will need to:
- Bundle these audio files with the application
- Provide a shared component that allows the selection of these sounds, or selecting a file
- Provide an option in the timer and alarms form to open this shared component to select sounds
- Add file location to the timer model
Bundling sounds should also fix xdg audio location issues with flatpaks.
Edited by Devin Lin