fix(mobile/telemetry): buffer pre-init events instead of dropping them

Root cause: TelemetryService.initialize() is async (device info collection,
SharedPreferences I/O, remote config sync), taking several hundred ms to
complete. RouteObserver page_view events and auth events fire synchronously
during the initial navigation before initialization finishes, causing the
"TelemetryService not initialized, event ignored" drops seen in logs.

Fix: add _preInitBuffer (max 50 events). logEvent() now enqueues events
instead of dropping when _isInitialized=false. After initialization
completes, all buffered events are replayed in order via logEvent(),
ensuring no startup events are lost.

The network errors ("Failed host lookup: api.gogenex.com") are unrelated —
they are expected in offline test environments and handled gracefully.

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

frontend/genex-mobile/lib/core/telemetry/telemetry_service.dart

@@ -45,6 +45,16 @@ class TelemetryService {
   bool _isInitialized = false;
   bool get isInitialized => _isInitialized;
 
+  /// 初始化完成前的事件缓冲队列
+  ///
+  /// 解决启动时序问题：initialize() 是异步的（需要收集设备信息、
+  /// 加载配置等），而 RouteObserver/auth 事件可能在初始化完成前
+  /// 就已触发。将这些事件缓存，初始化完成后统一 replay，确保不丢失。
+  ///
+  /// 上限 50 条，防止极端情况下内存积累。
+  final List<_PendingEvent> _preInitBuffer = [];
+  static const int _maxPreInitBuffer = 50;
+
   /// 会话管理器
   late SessionManager _sessionManager;
 
@@ -135,6 +145,16 @@ class TelemetryService {
     debugPrint('📊 TelemetryService initialized');
     debugPrint('   InstallId: $_installId');
     debugPrint('   UserId: $_userId');
+
+    // Replay 初始化前缓冲的事件（如 page_view、session 启动事件等）
+    if (_preInitBuffer.isNotEmpty) {
+      debugPrint('📊 [Telemetry] Replaying ${_preInitBuffer.length} buffered pre-init events');
+      final buffered = List<_PendingEvent>.from(_preInitBuffer);
+      _preInitBuffer.clear();
+      for (final e in buffered) {
+        logEvent(e.eventName, type: e.type, level: e.level, properties: e.properties);
+      }
+    }
   }
 
   /// 初始化 installId
@@ -167,7 +187,15 @@ class TelemetryService {
     Map<String, dynamic>? properties,
   }) {
     if (!_isInitialized) {
-      debugPrint('⚠️ TelemetryService not initialized, event ignored');
+      // 缓冲事件，等初始化完成后 replay，不丢弃
+      if (_preInitBuffer.length < _maxPreInitBuffer) {
+        _preInitBuffer.add(_PendingEvent(
+          eventName: eventName,
+          type: type,
+          level: level,
+          properties: properties,
+        ));
+      }
       return;
     }
 
@@ -394,3 +422,18 @@ class TelemetryService {
     _instance = null;
   }
 }
+
+/// 初始化前缓冲的待处理事件（内部使用）
+class _PendingEvent {
+  final String eventName;
+  final EventType type;
+  final EventLevel level;
+  final Map<String, dynamic>? properties;
+
+  const _PendingEvent({
+    required this.eventName,
+    required this.type,
+    required this.level,
+    this.properties,
+  });
+}