feat: 添加健康咨询页面及相关功能

- 在应用中新增健康咨询页面，展示用户健康数据和建议
- 集成 expo-linear-gradient 以实现页面背景渐变效果
- 更新 package.json 和 package-lock.json，添加 expo-linear-gradient 依赖
- 在首页中添加健康咨询的导航链接
- 修改布局以支持新页面的显示和交互

package-lock.json

@@ -20,6 +20,7 @@
         "expo-font": "~13.3.2",
         "expo-haptics": "~14.1.4",
         "expo-image": "~2.4.0",
+        "expo-linear-gradient": "^14.1.5",
         "expo-linking": "~7.1.7",
         "expo-router": "~5.1.4",
         "expo-splash-screen": "~0.30.10",
@@ -6310,6 +6311,17 @@
         "react": "*"
       }
     },
+    "node_modules/expo-linear-gradient": {
+      "version": "14.1.5",
+      "resolved": "https://mirrors.tencent.com/npm/expo-linear-gradient/-/expo-linear-gradient-14.1.5.tgz",
+      "integrity": "sha512-BSN3MkSGLZoHMduEnAgfhoj3xqcDWaoICgIr4cIYEx1GcHfKMhzA/O4mpZJ/WC27BP1rnAqoKfbclk1eA70ndQ==",
+      "license": "MIT",
+      "peerDependencies": {
+        "expo": "*",
+        "react": "*",
+        "react-native": "*"
+      }
+    },
     "node_modules/expo-linking": {
       "version": "7.1.7",
       "resolved": "https://registry.npmjs.org/expo-linking/-/expo-linking-7.1.7.tgz",