feat: partial album split view + artist page full-screen + Bibliothek iTunes integration

- Partial album detail: tapping incomplete albums now shows downloaded songs
  (normal playback) above and missing iTunes tracks (30s preview + download)
  below — on both Android and web PWA
- Android: ItunesArtistScreen now renders full-screen above the tab/search bar
- Android: ArtistDetailScreen (Bibliothek) now loads iTunes data in parallel —
  adds Weltweit populär section and In Library/Unvollständig/Nicht heruntergeladen
  album sections identical to the Erkunden artist page
- Fix: artist no longer appears in its own Similar Artists row
- Fix: duplicate album entries deduplicated by collectionId in categorizeAlbums

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

android/app/src/main/res/layout/activity_main.xml

@@ -1,12 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
-    android:layout_width="match_parent"
-    android:layout_height="match_parent"
-    android:background="#000000">
-
-    <WebView
-        android:id="@+id/web_view"
-        android:layout_width="match_parent"
-        android:layout_height="match_parent" />
-
-</FrameLayout>

android/app/src/main/res/values/font_certs.xml

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <array name="com_google_android_gms_fonts_certs">
+        <item>@array/com_google_android_gms_fonts_certs_dev</item>
+        <item>@array/com_google_android_gms_fonts_certs_prod</item>
+    </array>
+    <string-array name="com_google_android_gms_fonts_certs_dev">
+        <item>
+            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
+        </item>
+    </string-array>
+    <string-array name="com_google_android_gms_fonts_certs_prod">
+        <item>
+            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
+        </item>
+    </string-array>
+</resources>