feat: 后台管理页全量重构 + backoffice 共享模块 + 启动脚本优化

## 后台管理页重构
- admin 端: add_doctor / doctors / home / patients 四页重构
- doctor 端: consultations / dashboard / followup_edit / followups / home / patient_detail / patients / profile / report_detail / reports / settings 十一页重构
- 新增 backoffice 共享模块: backoffice_refresh_providers + backoffice_formatters + backoffice_ui

## 后端
- AdminService 增强(分页/搜索/统计)
- doctor_endpoints 微调
- appsettings.Development 调整
- 新增 admin_service_tests

## 前端其他
- 今日健康卡片 taskRow 行高 5->7(每行 44->48px)
- 健康仪表盘配色定 #4FACFE 纯色蓝
- admin_drawer / doctor_drawer 微调
- api_client IP 适配

## 启动脚本
- start-dev.bat: 加后端就绪检测(轮询 openapi 端点, 最多等 30s)

## 清理
- 删除旧品牌图(agent_welcome_abstract / login_background_v1)
- 删除 app_status_badge 组件
- 删除旧 HANDOFF 文档, 新增 07-17 版

## 测试
- 新增 backoffice_formatters / backoffice_refresh / backoffice_ui 三个测试
- app_router_test 扩展

health_app/test/app_router_test.dart

@@ -4,6 +4,8 @@ import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:health_app/core/app_router.dart';
 import 'package:health_app/core/navigation_provider.dart';
 import 'package:health_app/pages/report/report_pages.dart';
+import 'package:health_app/pages/doctor/doctor_followup_edit_page.dart';
+import 'package:health_app/pages/admin/admin_add_doctor_page.dart';
 
 void main() {
   testWidgets(
@@ -47,4 +49,51 @@ void main() {
     expect(page, isA<ReportListPage>());
     expect((page as ReportListPage).openUploadOnEnter, isTrue);
   });
+
+  testWidgets('follow-up editor route supports create mode without an id', (
+    tester,
+  ) async {
+    late Widget page;
+    await tester.pumpWidget(
+      ProviderScope(
+        child: Consumer(
+          builder: (context, ref, _) {
+            page = buildPage(const RouteInfo('doctorFollowUpEdit'), ref);
+            return const MaterialApp(home: SizedBox());
+          },
+        ),
+      ),
+    );
+
+    expect(page, isA<DoctorFollowUpEditPage>());
+    expect((page as DoctorFollowUpEditPage).id, isNull);
+  });
+
+  testWidgets('admin doctor form route supports edit mode', (tester) async {
+    late Widget page;
+    await tester.pumpWidget(
+      ProviderScope(
+        child: Consumer(
+          builder: (context, ref, _) {
+            page = buildPage(
+              const RouteInfo(
+                'adminAddDoctor',
+                params: {
+                  'id': 'doctor-1',
+                  'phone': '13800138000',
+                  'name': '王医生',
+                },
+              ),
+              ref,
+            );
+            return const MaterialApp(home: SizedBox());
+          },
+        ),
+      ),
+    );
+
+    expect(page, isA<AdminAddDoctorPage>());
+    expect((page as AdminAddDoctorPage).id, 'doctor-1');
+    expect((page as AdminAddDoctorPage).initialName, '王医生');
+  });
 }