feat: UI全面改造 + 后端多项修复

【后端修复】
- 删除diet/consultation agent假工具声明
- 修复DayOfWeek实体注释
- 修复Vision API content序列化
- cleanup_service级联删除修复
- 用药提醒时区偏差修复
- 统一DateTime处理(UtcNow+8)
- 新增UTC DateTime JSON转换器

【前端UI重构】
- 配色体系全面更新(#8B5CF6淡紫+#F0ECFF背景)
- 登录页重设计
- 首页重设计(透明顶栏、渐变背景、胶囊输入区)
- 聊天卡片加白蓝边框、渐变标题
- 侧边栏重构(渐变背景、合并顶部、删除底部设置)
- 确认卡片可编辑字段恢复
- 所有子页面加返回按钮
- catch异常加日志
- 删除后refresh provider缓存

health_app/pubspec.lock

@@ -145,6 +145,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "0.7.12"
+  dev_build:
+    dependency: transitive
+    description:
+      name: dev_build
+      sha256: f2742f154e484a52471dcc7eda17e6da06ab8b1d0a64b4845710d5de4fa9cc47
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.1.7+4"
   dio:
     dependency: "direct main"
     description:
@@ -653,6 +661,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.0.0"
+  native_toolchain_c:
+    dependency: transitive
+    description:
+      name: native_toolchain_c
+      sha256: f59351d28f49520cd3a74eb1f41c5f19ae15e53c65a3231d14af672e46510a96
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.19.1"
   node_preamble:
     dependency: transitive
     description:
@@ -821,6 +837,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.5.2"
+  process_run:
+    dependency: transitive
+    description:
+      name: process_run
+      sha256: e0e24c11a49445c449911daef46cf28d68e80a5e33daafbfbc6d6819a1f83519
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.3.3+1"
   pub_semver:
     dependency: transitive
     description:
@@ -978,6 +1002,22 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.5.8"
+  sqflite_common_ffi:
+    dependency: transitive
+    description:
+      name: sqflite_common_ffi
+      sha256: cd0c7f7de39a08f2d54ef144d9058c46eca8461879aaa648025643455c1e5a20
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.0+3"
+  sqflite_common_ffi_web:
+    dependency: "direct main"
+    description:
+      name: sqflite_common_ffi_web
+      sha256: "79338d0b69521d70cea10f841209ac87ce617921aaf7d33e7380682c83da1f06"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.1.1"
   sqflite_darwin:
     dependency: transitive
     description:
@@ -994,6 +1034,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.4.0"
+  sqlite3:
+    dependency: transitive
+    description:
+      name: sqlite3
+      sha256: "9488c7d2cdb1091c91cacf7e207cff81b28bff8e366f042bad3afe7d34afe189"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.3.2"
   sse:
     dependency: transitive
     description: