v2.31 — Login, Einstellungen & Cloud Sync Redesign

- Login-Screen im Melo-Design (Schwarz+Rot) mit Baka-Auth JWT
- AuthService fuer Token-Management ueber baka-net.de/auth
- Registrierungs-Modus + 'Ohne Login fortfahren'
- Navidrome-Credentials optional im Login aufklappbar

- SettingsScreen ersetzt AlertDialog
- BottomNav navigiert statt Dialog zu triggern
- Cloud Sync, Server verbinden, Diagnosedaten, App-Info, Abmelden

- CloudEinstellungen-Dialog entfernt, alles in CloudScreen konsolidiert
- Hardcode login('Baka','') entfernt → AuthService.benutzer
- Gradient-Statuskarte, animierte Segment-Intervall-Auswahl
- JWT Authorization statt Klartext-Passwort

- AppConfig: API-Key defaultValue entfernt (kein Fallback-Leak)
- Build crasht ohne --dart-define MELO_API_KEY

Build: split APK (arm64 19.6M, armeabi 17.1M, x86_64 21.1M)

macos_old_backup/Runner/Assets.xcassets/AppIcon.appiconset/Contents.json

@@ -0,0 +1,68 @@
+{
+  "images" : [
+    {
+      "size" : "16x16",
+      "idiom" : "mac",
+      "filename" : "app_icon_16.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "16x16",
+      "idiom" : "mac",
+      "filename" : "app_icon_32.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "32x32",
+      "idiom" : "mac",
+      "filename" : "app_icon_32.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "32x32",
+      "idiom" : "mac",
+      "filename" : "app_icon_64.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "128x128",
+      "idiom" : "mac",
+      "filename" : "app_icon_128.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "128x128",
+      "idiom" : "mac",
+      "filename" : "app_icon_256.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "256x256",
+      "idiom" : "mac",
+      "filename" : "app_icon_256.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "256x256",
+      "idiom" : "mac",
+      "filename" : "app_icon_512.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "512x512",
+      "idiom" : "mac",
+      "filename" : "app_icon_512.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "512x512",
+      "idiom" : "mac",
+      "filename" : "app_icon_1024.png",
+      "scale" : "2x"
+    }
+  ],
+  "info" : {
+    "version" : 1,
+    "author" : "xcode"
+  }
+}