fix: 清零 flutter analyze 问题并修复隐私红线正则缺陷（CI 门禁）

- 修复真实缺陷：隐私红线 RegExp 使用 Dart 不支持的 (?i) 内联标志，构造即抛异常
  导致带 props 的事件被静默丢弃；改为 caseSensitive: false
- 清理埋点模块未用 import/字段/变量（4 warning）
- 构造函数改用初始化形参（含 Dart 3.12 私有具名参数）
- E2E 手动脚本声明 ignore avoid_print + library 指令
- 门禁：format 0 changed / analyze No issues / flutter test 34 passed

lib/analytics/analytics_service.dart

@@ -1,7 +1,6 @@
 import 'dart:convert';
 import 'dart:io';
 import 'package:flutter/foundation.dart';
-import 'package:shared_preferences/shared_preferences.dart';
 import 'package:uuid/uuid.dart';
 
 /// Simplified analytics client for M0 (report 13 + ticket 19): track events
@@ -10,21 +9,18 @@ import 'package:uuid/uuid.dart';
 /// silently discarded (no retry as spec'd); privacy red-line enforced locally.
 class AnalyticsService {
   AnalyticsService({
-    required String apiBaseUrl,
+    required this.apiBaseUrl,
     required this.getAccessToken,
     String? anonymousId,
-    String? userId,
-  }) : _apiBaseUrl = apiBaseUrl,
-       _anonymousId = anonymousId ?? const Uuid().v4(),
-       _userId = userId;
+    this._userId,
+  }) : _anonymousId = anonymousId ?? const Uuid().v4();
 
-  static const _queueKey = 'patbond_analytics_queue';
-  static const _queueMaxSize = 500;
+  // M0：内存队列，满 _flushThreshold 条上传一次；持久化队列留 M1（报告 19 §3）。
   static const _flushThreshold = 20;
 
-  final String _apiBaseUrl;
+  final String apiBaseUrl;
   final String Function()? getAccessToken;
-  String _anonymousId;
+  final String _anonymousId;
   String? _userId;
   final List<Map<String, dynamic>> _pendingEvents = [];
 
@@ -90,13 +86,8 @@ class AnalyticsService {
 
   Future<void> _upload(List<Map<String, dynamic>> events) async {
     final token = getAccessToken?.call();
-    final headers = {
-      'Content-Type': 'application/json',
-      if (token != null) 'Authorization': 'Bearer $token',
-    };
-
     final request =
-        await HttpClient().postUrl(Uri.parse('$_apiBaseUrl/api/v1/events'))
+        await HttpClient().postUrl(Uri.parse('$apiBaseUrl/api/v1/events'))
           ..headers.contentType = ContentType.json;
     if (token != null) {
       request.headers.add('Authorization', 'Bearer $token');
@@ -110,8 +101,10 @@ class AnalyticsService {
   }
 
   bool _containsForbiddenField(Map<String, dynamic> props) {
+    // Dart RegExp 不支持 (?i) 内联标志（原写法构造即抛异常，事件被静默丢弃）。
     final pattern = RegExp(
-      r'(?i).*(password|token|secret|phone|mobile|email|credential|idfa|gaid).*',
+      r'password|token|secret|phone|mobile|email|credential|idfa|gaid',
+      caseSensitive: false,
     );
     return props.keys.any((key) => pattern.hasMatch(key));
   }