feat(conquerPackage, upload): 新增课前课中页面与多图上传组件，修复路由配置

- 实现攻克包模块的课前课中学习页面，包含学习计时、笔记上传、分页切换等完整逻辑
- 新增通用多图上传组件，支持编辑/查看两种业务模式
- 配置新页面的路由规则，并更新捕获列表页面的跳转逻辑为正式的go_router跳转
- 修复捕获列表页面跳转路径不匹配的问题

lib/core/router/app_router.dart

@@ -14,6 +14,7 @@ import 'package:new_learn/features/class/my_update_detail_page.dart';
 import 'package:new_learn/core/api/class/model.dart';
 import 'package:new_learn/features/my/my_page.dart';
 import 'package:new_learn/features/conquerPackage/captureList/index.dart';
+import 'package:new_learn/features/conquerPackage/beforeDuringClass/index.dart';
 import 'package:new_learn/features/my/my_point/my_point_page.dart';
 import 'package:new_learn/features/my/my_report/my_report_page.dart';
 import 'package:new_learn/features/my/my_report/report_detail_page.dart';
@@ -169,6 +170,13 @@ final GoRouter appRouter = GoRouter(
       builder: (_, state) =>
           CaptureListPage(courseId: state.extra as String),
     ),
+    // ---------- 攻克包 - 课前课中 ----------
+    GoRoute(
+      path: '/conquerPackage/beforeDuringClass',
+      builder: (_, state) => BeforeDuringClassPage(
+        extra: state.extra as Map<String, dynamic>?,
+      ),
+    ),
     GoRoute(path: '/register', builder: (_, _) => const RegisterPage()),
 
     // app_router.dart 的 routes 里加，不用管跳转逻辑