Migration to last.fm, removed old spotify api client. FOSRestBundle API serving data driven front end (JWT).

docs/troubleshooting.md

@@ -29,9 +29,8 @@
   postgresql://symfony:symfony@db:5432/symfony?serverVersion=16&charset=utf8
   ```
 
-## Spotify errors
-- Verify credentials in `/admin/settings` or env vars `SPOTIFY_CLIENT_ID` / `SPOTIFY_CLIENT_SECRET`.
-- Client Credentials tokens are cached; if revoked, wait for expiry or restart the container.
+## Last.fm errors
+- Verify credentials in `/admin/settings` or env var `LASTFM_API_KEY`.
 
 ## ARM64 Build
 
@@ -43,4 +42,4 @@ sudo docker buildx build \
     -f docker/php/Dockerfile \
     . \
     --load
-```
+```