feat: Added reduce shadows setting. Added a new setting to reduce sha…

…dows drawn by the app to improve performance.

- Added a new preference key `REDUCE_SHADOWS` with a default value of `false`.
- Added a new switch in the General settings page to control the setting.
- Modified `CompactSongCard` to conditionally apply shadows based on the setting.
- Updated translations for the new setting.

Update codeql.yml

chore: Updated to beta 6

Signed-off-by: Gabriel Fontán <[email protected]>

perf: Improved song loading by moving memory-expensive functions to t…

…he VM

Signed-off-by: Gabriel Fontán <[email protected]>

(readme): Fixed h2 not being well shown

Signed-off-by: Gabriel Fontán <[email protected]>