feat(app): OS session-expiry enforcement, session persistence, support sync

Enforce session expiry at the OS level (AlarmManager + handler) so the tunnel dies even if the UI process is killed; persist the session so a START_STICKY restart re-establishes it; sync immediately after a support top-up; slow the session beacon 5s/30s -> 60s/60s; drop the Always-on-VPN deep-link and the legacy 'ass' migration. Docs: CHANGELOG 3.3.4, privacy-policy log disclosure, README.

tool/patch_flutter_vless_runtime_recovery.dart

@@ -0,0 +1,119 @@
+import 'dart:convert';
+import 'dart:io';
+
+const packageName = 'flutter_vless_android';
+const expectedVersionFragment = 'flutter_vless_android-1.1.5';
+
+Never fail(String message) {
+  stderr.writeln('[flutter_vless recovery patch] $message');
+  exit(1);
+}
+
+Directory packageRoot() {
+  final configFile = File('.dart_tool/package_config.json');
+  if (!configFile.existsSync()) {
+    fail('.dart_tool/package_config.json is missing; run flutter pub get first');
+  }
+
+  final decoded = jsonDecode(configFile.readAsStringSync());
+  if (decoded is! Map<String, dynamic> || decoded['packages'] is! List) {
+    fail('package_config.json is invalid');
+  }
+
+  Map<String, dynamic>? package;
+  for (final item in decoded['packages'] as List) {
+    if (item is Map && item['name'] == packageName) {
+      package = Map<String, dynamic>.from(item);
+      break;
+    }
+  }
+  if (package == null) fail('$packageName was not found');
+
+  final rootUriValue = package['rootUri'];
+  if (rootUriValue is! String || rootUriValue.isEmpty) {
+    fail('$packageName has no rootUri');
+  }
+
+  final rootUri = Uri.parse(rootUriValue);
+  final resolved = rootUri.hasScheme
+      ? rootUri
+      : configFile.parent.absolute.uri.resolveUri(rootUri);
+  if (resolved.scheme != 'file') fail('unsupported package URI: $resolved');
+
+  final root = Directory.fromUri(resolved);
+  final normalized = root.absolute.path.replaceAll('\\', '/');
+  if (!normalized.contains(expectedVersionFragment)) {
+    fail('expected flutter_vless_android 1.1.5, got ${root.path}');
+  }
+  if (!root.existsSync()) fail('package root does not exist: ${root.path}');
+  return root;
+}
+
+void replaceOnce(
+  File file,
+  String oldValue,
+  String newValue,
+  String marker,
+) {
+  if (!file.existsSync()) fail('missing upstream source: ${file.path}');
+  final text = file.readAsStringSync();
+  if (text.contains(marker)) {
+    stdout.writeln('[flutter_vless recovery patch] already current: ${file.path}');
+    return;
+  }
+  if (!text.contains(oldValue)) {
+    fail('upstream source changed; expected block not found in ${file.path}');
+  }
+  file.writeAsStringSync(text.replaceFirst(oldValue, newValue));
+  stdout.writeln('[flutter_vless recovery patch] patched: ${file.path}');
+}
+
+void main() {
+  final root = packageRoot();
+  final kotlin = Directory(
+    '${root.path}/android/src/main/kotlin/com/github/tfox/flutter_vless',
+  );
+
+  final serviceFile = File('${kotlin.path}/xray/service/XrayVPNService.kt');
+  if (!serviceFile.existsSync()) {
+    fail('pinned Android runtime service source is missing');
+  }
+
+  // A fast reconnect must not leave the previous Xray process owning the local
+  // SOCKS/HTTP ports.
+  replaceOnce(
+    serviceFile,
+    '''            if (config != null) {
+                // Ensure clean state before starting
+                cleanup()
+''',
+    '''            if (config != null) {
+                // A fast reconnect must not leave the previous Xray process
+                // owning the local SOCKS/HTTP ports.
+                if (XrayCoreManager.isXrayRunning()) {
+                    Log.w(TAG, "Stopping stale Xray core before restart")
+                    XrayCoreManager.stopCore(this)
+                }
+                cleanup()
+''',
+    'Stopping stale Xray core before restart',
+  );
+
+  // The tun2socks Unix socket must not survive a previous session.
+  replaceOnce(
+    serviceFile,
+    '''        val tun2socksPath = File(applicationInfo.nativeLibraryDir, "libtun2socks.so").absolutePath
+        val sockPath = File(filesDir, "sock_path").absolutePath
+''',
+    '''        val tun2socksPath = File(applicationInfo.nativeLibraryDir, "libtun2socks.so").absolutePath
+        val socketFile = File(filesDir, "sock_path")
+        if (socketFile.exists() && !socketFile.delete()) {
+            Log.w(TAG, "Could not delete stale tun2socks socket")
+        }
+        val sockPath = socketFile.absolutePath
+''',
+    'Could not delete stale tun2socks socket',
+  );
+
+  stdout.writeln('[flutter_vless recovery patch] runtime recovery patch is ready');
+}