[FEATURE] Save editing settings across sessions

[ShockedCoder]

I only ever use the 90° rotation snap angle, so it gets very repetitive to have to re-set that setting whenever I start editing.

[UmerCodez]

Making this setting persistent would require adding a new field to the database table associated with control pads, creating a Room migration, and writing tests for the migration.

Anyone interested in adding this feature is welcome to submit a PR!