feat: implement DeezerDownloadService with Blowfish decryption

- Port JavaScript DeezerDownloader to C#
- Add Deezer API authentication with ARL token
- Implement track download via media.deezer.com API
- Add Blowfish CBC decryption for encrypted chunks (uses OpenSSL)
- Add rate limiting and retry with exponential backoff
- Update config for Deezer ARL tokens
- Configure Subsonic URL to 192.168.1.12:4533

octo-fiesta/appsettings.json

@@ -7,12 +7,13 @@
   },
   "AllowedHosts": "*",
   "Subsonic": {
-    "Url": "http://localhost:4533"
+    "Url": "http://192.168.1.12:4533"
   },
   "Library": {
     "DownloadPath": "./downloads"
   },
-  "Deezspot": {
-    "ExecutablePath": ""
+  "Deezer": {
+    "Arl": "",
+    "ArlFallback": ""
   }
 }