combine userdata and swing db into one

+ port populate to new db interface
+ add genrehashes and hash info to tracks
+ properly structure new db table files
+ move helpers to dedicated utils file
+ move settings from db to config file
+ move artists, albums, auth and favorites endpoint to new db interface
+ use folder store to index filepaths
+ paginate favorite pages
+ 56 moretiny changes 😅

app/models/lastfm.py

@@ -1,13 +1,28 @@
 from dataclasses import dataclass
+from typing import Any
+
+
+@dataclass
+class SimilarArtistEntry:
+    artisthash: str
+    name: str
+    weight: float
+    scrobbles: int
+    listeners: int
 
 
 @dataclass
 class SimilarArtist:
     artisthash: str
-    similar_artist_hashes: str
+    similar_artists: list[SimilarArtistEntry]
+
 
     def get_artist_hash_set(self) -> set[str]:
         """
         Returns a set of similar artists.
         """
-        return set(self.similar_artist_hashes.split("~"))
+        if not self.similar_artists:
+            return set()
+
+        # INFO: 
+        return set(a['artisthash'] for a in self.similar_artists)