load settings from db, use api to change settings

+ add route to get all settings
+ add route to set any setting
+ add untested migration to add settings into settings db
+ compress json in api responses using FlaskCompress
+ serve gziped assets if browser accepts encoded files
+ misc

app/migrations/__init__.py

@@ -25,6 +25,7 @@ migrations: list[list[Migration]] = [
         v1_3_0.AddLastUpdatedToTrackTable,
         v1_3_0.MovePlaylistsAndFavoritesTo10BitHashes,
         v1_3_0.RemoveAllTracks,
+        v1_3_0.UpdateAppSettingsTable,
     ]
 ]