risolti alcuni problemi di SessionManager

backend/auth/session.py

@@ -57,7 +57,7 @@ class SessionData():
 
 class SessionManager():
     __current_session: SessionData
-    __instance: "SessionManager"
+    __instance: "SessionManager" = None
 
     def __new__(cls, *args, **kwargs):
         if cls.__instance is None:

backend/endpoints/spotify_api.py

@@ -14,7 +14,7 @@ SPOTIFY_TOKEN_URL = "https://accounts.spotify.com/api/token"
 SPOTIFY_PLAY_URL = "https://api.spotify.com/v1/me/player/play"
 
 # Step 1: Redirect user to Spotify login
-@music_router.post("/login")
+@music_router.get("/login")
 def login():
     scope = "user-modify-playback-state user-read-playback-state"
     url = (
@@ -26,7 +26,7 @@ def login():
     return RedirectResponse(url)
 
 # Step 2: Callback to get access token
-@music_router.post("/callback")
+@music_router.get("/callback")
 def callback(code: str):
     payload = {
         "grant_type": "authorization_code",