0.6.1: Fix Spotify OAuth scope missing user-library-read

connect.py's OAuth scope request (playlist-read-private
playlist-read-collaborative) didn't match what sldl's own built-in login
flow requests (same two, plus user-library-read). The narrower scope alembic
granted let sldl refresh a valid access token, but Spotify then returned 403
Forbidden loading the playlist regardless of ownership, which sldl turns
into an unhandled-exception crash (exit 134) instead of a clean scope error.
Found by reproducing a friend's crash: his playlist was his own, connected
via his own OAuth, correct redirect URI -- ruling out the ownership/
visibility explanation and pointing at the scope mismatch instead.

Also:
- run-playlist.sh: detect exit 134 specifically and log a pointed hint
  (distinguishing the Forbidden-loading-playlist case from any other
  unhandled sldl exception) instead of just "sldl finished with exit code
  134" with no context.
- README: document that anyone who connected Spotify before this version
  needs to click Connect Spotify again -- existing refresh tokens carry the
  old, narrower scope and don't upgrade themselves.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

app/routers/connect.py

@@ -25,7 +25,13 @@ router = APIRouter(tags=["spotify-connect"])
 
 AUTHORIZE_URL = "https://accounts.spotify.com/authorize"
 TOKEN_URL = "https://accounts.spotify.com/api/token"
-SCOPES = "playlist-read-private playlist-read-collaborative"
+# Matches exactly what sldl's own built-in OAuth login flow requests (seen in
+# its printed authorize URL: user-library-read + these two) -- granting a
+# narrower scope than sldl expects gets a token sldl can refresh fine but
+# then gets 403 Forbidden from Spotify partway through loading a playlist,
+# which sldl turns into an unhandled-exception crash (exit 134) rather than a
+# clean scope error.
+SCOPES = "playlist-read-private playlist-read-collaborative user-library-read"
 
 
 def _callback_redirect_uri(request: Request) -> str: