Add v9.0: Auto-update system with Gitea integration

- Implement UpdateManager to check Gitea releases for new versions
- Add update dialogs with mandatory/optional update support
- Integrate DownloadManager for APK downloads
- Add FileProvider configuration for app installation
- Support update-manifest.json for version control enforcement
- Add comprehensive update strings and error handling
- Include gradlew executable permissions

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

app/src/main/AndroidManifest.xml

@@ -5,6 +5,7 @@
     <uses-permission android:name="android.permission.INTERNET" />
     <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
     <uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />
+    <uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES" />
     <uses-feature
         android:name="android.software.leanback"
         android:required="false" />
@@ -22,6 +23,16 @@
         android:theme="@style/Theme.StreamPlayer"
         android:usesCleartextTraffic="true">
 
+        <provider
+            android:name="androidx.core.content.FileProvider"
+            android:authorities="${applicationId}.fileprovider"
+            android:exported="false"
+            android:grantUriPermissions="true">
+            <meta-data
+                android:name="android.support.FILE_PROVIDER_PATHS"
+                android:resource="@xml/file_paths" />
+        </provider>
+
         <activity
             android:name=".PlayerActivity"
             android:exported="false"