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/java/com/streamplayer/MainActivity.java

@@ -1,10 +1,13 @@
 package com.streamplayer;
 
+import android.app.AlertDialog;
 import android.content.Intent;
+import android.net.Uri;
 import android.os.Bundle;
 import android.view.View;
 import android.widget.ProgressBar;
 import android.widget.TextView;
+import android.widget.Toast;
 
 import androidx.appcompat.app.AppCompatActivity;
 import androidx.recyclerview.widget.GridLayoutManager;
@@ -35,6 +38,8 @@ public class MainActivity extends AppCompatActivity {
     private final List<EventItem> cachedEvents = new ArrayList<>();
     private List<SectionEntry> sections;
     private SectionEntry currentSection;
+    private UpdateManager updateManager;
+    private AlertDialog updateDialog;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -60,6 +65,45 @@ public class MainActivity extends AppCompatActivity {
         sectionList.setAdapter(sectionAdapter);
 
         selectSection(0);
+
+        updateManager = new UpdateManager(this);
+        updateManager.checkForUpdates(new UpdateManager.UpdateCallback() {
+            @Override
+            public void onUpdateAvailable(UpdateManager.UpdateInfo info) {
+                handleUpdateInfo(info);
+            }
+
+            @Override
+            public void onUpToDate() {
+                // Nothing to do.
+            }
+
+            @Override
+            public void onError(String message) {
+                Toast.makeText(MainActivity.this,
+                        getString(R.string.update_error_checking, message),
+                        Toast.LENGTH_SHORT).show();
+            }
+        });
+    }
+
+    @Override
+    protected void onResume() {
+        super.onResume();
+        if (updateManager != null) {
+            updateManager.resumePendingInstall(this);
+        }
+    }
+
+    @Override
+    protected void onDestroy() {
+        super.onDestroy();
+        if (updateDialog != null && updateDialog.isShowing()) {
+            updateDialog.dismiss();
+        }
+        if (updateManager != null) {
+            updateManager.release();
+        }
     }
 
     private void selectSection(int index) {
@@ -151,6 +195,87 @@ public class MainActivity extends AppCompatActivity {
         startActivity(intent);
     }
 
+    private void handleUpdateInfo(UpdateManager.UpdateInfo info) {
+        if (info == null) {
+            return;
+        }
+        boolean forceUpdate = info.isMandatory(BuildConfig.VERSION_CODE);
+        showUpdateDialog(info, forceUpdate);
+    }
+
+    private void showUpdateDialog(UpdateManager.UpdateInfo info, boolean mandatory) {
+        if (isFinishing()) {
+            return;
+        }
+        if (updateDialog != null && updateDialog.isShowing()) {
+            updateDialog.dismiss();
+        }
+        AlertDialog.Builder builder = new AlertDialog.Builder(this)
+                .setTitle(mandatory ? R.string.update_required_title : R.string.update_available_title)
+                .setMessage(buildUpdateMessage(info))
+                .setPositiveButton(R.string.update_action_download,
+                        (dialog, which) -> updateManager.downloadUpdate(MainActivity.this, info))
+                .setNeutralButton(R.string.update_action_view_release,
+                        (dialog, which) -> openReleasePage(info));
+        if (mandatory) {
+            builder.setCancelable(false);
+            builder.setNegativeButton(R.string.update_action_close_app,
+                    (dialog, which) -> finish());
+        } else {
+            builder.setNegativeButton(R.string.update_action_later, null);
+        }
+        updateDialog = builder.show();
+    }
+
+    private CharSequence buildUpdateMessage(UpdateManager.UpdateInfo info) {
+        StringBuilder builder = new StringBuilder();
+        builder.append(getString(R.string.update_current_version,
+                BuildConfig.VERSION_NAME, BuildConfig.VERSION_CODE));
+        builder.append('\n');
+        builder.append(getString(R.string.update_latest_version,
+                info.versionName, info.versionCode));
+        if (info.minSupportedVersionCode > 0) {
+            builder.append('\n').append(getString(R.string.update_min_supported,
+                    info.minSupportedVersionCode));
+        }
+        String size = info.formatSize(this);
+        if (!size.isEmpty()) {
+            builder.append('\n').append(getString(R.string.update_download_size, size));
+        }
+        if (info.downloadCount > 0) {
+            builder.append('\n').append(getString(R.string.update_downloads,
+                    info.downloadCount));
+        }
+        if (!info.releaseNotes.isEmpty()) {
+            builder.append("\n\n");
+            builder.append(getString(R.string.update_release_notes_title));
+            builder.append('\n');
+            builder.append(info.getReleaseNotesPreview());
+        }
+        if (!info.isMandatory(BuildConfig.VERSION_CODE)) {
+            builder.append("\n\n");
+            builder.append(getString(R.string.update_optional_hint));
+        }
+        return builder.toString();
+    }
+
+    private void openReleasePage(UpdateManager.UpdateInfo info) {
+        String url = info.releasePageUrl;
+        if (url == null || url.isEmpty()) {
+            url = info.downloadUrl;
+        }
+        if (url == null || url.isEmpty()) {
+            Toast.makeText(this, R.string.update_error_missing_url, Toast.LENGTH_SHORT).show();
+            return;
+        }
+        Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
+        try {
+            startActivity(intent);
+        } catch (Exception e) {
+            Toast.makeText(this, R.string.update_error_open_release, Toast.LENGTH_SHORT).show();
+        }
+    }
+
     private int getSpanCount() {
         return getResources().getInteger(R.integer.channel_grid_span);
     }