v1.2.1: MusicBrainz genre enrichment + cleanup

## Features
- Implement automatic MusicBrainz genre enrichment for all external sources
  - Deezer: Enriches when genre missing
  - Qobuz: Enriches when genre missing
  - SquidWTF/Tidal: Always enriches (Tidal doesn't provide genres)
- Use ISRC codes for exact matching, fallback to title/artist search
- Cache results in Redis (30 days) + file cache for performance
- Respect MusicBrainz rate limits (1 req/sec)

## Cleanup
- Remove unused Spotify API ClientId and ClientSecret settings
- Simplify Spotify API configuration

This ensures all external tracks have genre metadata for better
organization and filtering in music clients.

.env.example

@@ -35,24 +35,12 @@ JELLYFIN_LIBRARY_ID=
 # Music service to use: SquidWTF, Deezer, or Qobuz (default: SquidWTF)
 MUSIC_SERVICE=SquidWTF
 
-<<<<<<< HEAD
-# Base directory for all downloads (default: ./downloads)
-# This creates three subdirectories:
-# - downloads/permanent/ - Permanently downloaded tracks (STORAGE_MODE=Permanent)
-# - downloads/cache/ - Temporarily cached tracks (STORAGE_MODE=Cache)
-# - downloads/kept/ - Favorited external tracks (always permanent)
-DOWNLOAD_PATH=./downloads
-||||||| bc4e5d9
-# Path where downloaded songs will be stored on the host (only applies if STORAGE_MODE=Permanent)
-DOWNLOAD_PATH=./downloads
-=======
 # Base directory for all downloads (default: ./downloads)
 # This creates three subdirectories:
 # - downloads/permanent/ - Permanently downloaded tracks (STORAGE_MODE=Permanent)
 # - downloads/cache/ - Temporarily cached tracks (STORAGE_MODE=Cache)
 # - downloads/kept/ - Favorited external tracks (always permanent)
 Library__DownloadPath=./downloads
->>>>>>> dev
 
 # ===== SQUIDWTF CONFIGURATION =====
 # Different quality options for SquidWTF. Only FLAC supported right now
@@ -155,13 +143,6 @@ SPOTIFY_IMPORT_PLAYLISTS=[]
 # Enable direct Spotify API access (default: false)
 SPOTIFY_API_ENABLED=false
 
-# Spotify Client ID from https://developer.spotify.com/dashboard
-# Create an app in the Spotify Developer Dashboard to get this
-SPOTIFY_API_CLIENT_ID=
-
-# Spotify Client Secret (optional - only needed for certain OAuth flows)
-SPOTIFY_API_CLIENT_SECRET=
-
 # Spotify session cookie (sp_dc) - REQUIRED for editorial playlists
 # Editorial playlists (Release Radar, Discover Weekly, etc.) require authentication
 # via session cookie because they're not accessible through the official API.