feat: Cupertino滚轮选择器 + 品牌更名 + UI全面优化

- 日期/时间/次数选择器统一改为底部弹出Cupertino滚轮，无单位标签，双横线选区
- App更名为"小脉健康"，副标题"血管病患者的AI健康管理助手"
- 健康仪表盘及侧边栏移除体重指标，侧边栏背景改为蓝白渐变
- 健康档案按钮移入功能入口网格，与其他入口样式统一
- 记数据智能体配色改为绿色渐变(#A1FFCE→#69DB8F)
- 隐私协议/关于页从Text改为MarkdownBody正确渲染
- 运动计划/饮食记录卡片添加边框和阴影
- 服药次数从chip改为滚轮选择器
- 日期显示格式统一为空格分隔(1999 01 01)
- 健康档案页背景改为纯白

health_app/lib/pages/medication/medication_edit_page.dart

@@ -159,14 +159,22 @@ class _MedicationEditPageState extends ConsumerState<MedicationEditPage> {
           const SizedBox(height: 16),
           // 频率选择
           _label('每日服药次数'), const SizedBox(height: 8),
-          Wrap(
-            spacing: 8,
-            children: List.generate(
-              4,
-              (i) => _chip(
-                '${i + 1}次',
-                _timesPerDay == i + 1,
-                () => _updateTimes(i + 1),
+          GestureDetector(
+            onTap: () async {
+              final n = await showAppCountPicker(context, initialValue: _timesPerDay, min: 1, max: 4, label: ' 次');
+              if (n != null) _updateTimes(n);
+            },
+            child: Container(
+              width: double.infinity,
+              padding: const EdgeInsets.all(12),
+              decoration: BoxDecoration(
+                color: AppTheme.surface,
+                borderRadius: BorderRadius.circular(AppTheme.rMd),
+                border: Border.all(color: AppColors.border),
+              ),
+              child: Text(
+                '$_timesPerDay 次/天',
+                style: const TextStyle(fontSize: 18),
               ),
             ),
           ),
@@ -180,8 +188,8 @@ class _MedicationEditPageState extends ConsumerState<MedicationEditPage> {
               _timesPerDay,
               (i) => GestureDetector(
                 onTap: () async {
-                  final t = await showTimePicker(
-                    context: context,
+                  final t = await showAppTimePicker(
+                    context,
                     initialTime: _times[i],
                   );
                   if (t != null) setState(() => _times[i] = t);
@@ -324,8 +332,8 @@ class _MedicationEditPageState extends ConsumerState<MedicationEditPage> {
           const SizedBox(height: 6),
           GestureDetector(
             onTap: () async {
-              final d = await showDatePicker(
-                context: context,
+              final d = await showAppDatePicker(
+                context,
                 initialDate: val,
                 firstDate: DateTime(2024),
                 lastDate: DateTime(2030),
@@ -341,7 +349,7 @@ class _MedicationEditPageState extends ConsumerState<MedicationEditPage> {
                 border: Border.all(color: AppColors.border),
               ),
               child: Text(
-                '${val.month}/${val.day}',
+                '${val.year} ${val.month.toString().padLeft(2, '0')} ${val.day.toString().padLeft(2, '0')}',
                 style: const TextStyle(fontSize: 18),
               ),
             ),
@@ -359,8 +367,8 @@ class _MedicationEditPageState extends ConsumerState<MedicationEditPage> {
       const SizedBox(height: 6),
       GestureDetector(
         onTap: () async {
-          final d = await showDatePicker(
-            context: context,
+          final d = await showAppDatePicker(
+            context,
             initialDate: val ?? DateTime.now(),
             firstDate: DateTime(2024),
             lastDate: DateTime(2030),
@@ -378,7 +386,7 @@ class _MedicationEditPageState extends ConsumerState<MedicationEditPage> {
           child: Row(
             children: [
               Text(
-                val != null ? '${val.month}/${val.day}' : '不设置',
+                val != null ? '${val.year} ${val.month.toString().padLeft(2, '0')} ${val.day.toString().padLeft(2, '0')}' : '不设置',
                 style: TextStyle(
                   fontSize: 18,
                   color: val != null ? null : AppTheme.textHint,