feat: 用药提醒功能 + 移除医生相关页面

- 后端新增 GET /api/medications/reminders 接口
- 前端任务卡片区显示真实用药提醒
- 移除 DoctorListPage/DoctorChatPage 路由
- 移除"找医生"面板按钮
- 医生端另做 Web 页面

health_app/lib/pages/chart/trend_page.dart

@@ -15,6 +15,7 @@ class _TrendPageState extends ConsumerState<TrendPage> {
   int _period = 7;
   bool _showAllRecords = false;
   late List<Map<String, dynamic>> _data;
+  final _chartKey = GlobalKey();
 
   static const _labels = {
     'blood_pressure': '血压趋势',
@@ -420,20 +421,24 @@ class _TrendPageState extends ConsumerState<TrendPage> {
             ],
           ),
           const SizedBox(height: 12),
-          SizedBox(
-            height: 200,
-            child: CustomPaint(
-              painter: _TrendChartPainter(
-                data: _data,
-                metricType: widget.metricType,
-                isDualLine: _isDualLine,
-                yMin: yRange.min,
-                yMax: yRange.max,
-                yStep: yRange.step,
-                formatDateLabel: _formatDateLabel,
-                formatValue: _formatValue,
+          GestureDetector(
+            key: _chartKey,
+            onTapDown: (details) => _onChartTap(details, yRange),
+            child: SizedBox(
+              height: 200,
+              child: CustomPaint(
+                painter: _TrendChartPainter(
+                  data: _data,
+                  metricType: widget.metricType,
+                  isDualLine: _isDualLine,
+                  yMin: yRange.min,
+                  yMax: yRange.max,
+                  yStep: yRange.step,
+                  formatDateLabel: _formatDateLabel,
+                  formatValue: _formatValue,
+                ),
+                size: Size.infinite,
               ),
-              size: Size.infinite,
             ),
           ),
         ],
@@ -570,6 +575,101 @@ class _TrendPageState extends ConsumerState<TrendPage> {
       ),
     );
   }
+
+  // ==================== 图表点击检测 ====================
+  void _onChartTap(TapDownDetails details, ({double min, double max, double step}) yRange) {
+    final renderBox = _chartKey.currentContext?.findRenderObject() as RenderBox?;
+    if (renderBox == null || _data.length < 2) return;
+
+    final localPosition = renderBox.globalToLocal(details.globalPosition);
+
+    const leftPadding = 44.0;
+    const rightPadding = 8.0;
+    final chartW = renderBox.size.width - leftPadding - rightPadding;
+
+    // 找到 x 方向最近的数据点
+    int nearestIndex = 0;
+    double minDist = double.infinity;
+    for (int i = 0; i < _data.length; i++) {
+      final pointX = leftPadding + (chartW * i / (_data.length - 1));
+      final dist = (localPosition.dx - pointX).abs();
+      if (dist < minDist) {
+        minDist = dist;
+        nearestIndex = i;
+      }
+    }
+
+    // 点击偏离数据点太远则不响应
+    if (minDist > 40) return;
+
+    final item = _data[nearestIndex];
+    final date = item['date'] as DateTime;
+    final val = item['value'] as num;
+    final val2 = item['value2'] as num?;
+    final status = _getStatus(val, value2: val2);
+
+    String displayValue;
+    if (_isDualLine) {
+      displayValue = '${_formatValue(val)} / ${_formatValue(val2 ?? 0)} ${_getUnit()}';
+    } else {
+      displayValue = '${_formatValue(val)} ${_getUnit()}';
+    }
+
+    showDialog(
+      context: context,
+      builder: (ctx) => AlertDialog(
+        title: Text(
+          _formatDateTime(date),
+          style: const TextStyle(fontSize: 16, fontWeight: FontWeight.w600, color: Color(0xFF1A1A1A)),
+        ),
+        content: Column(
+          mainAxisSize: MainAxisSize.min,
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            Text(
+              displayValue,
+              style: const TextStyle(fontSize: 28, fontWeight: FontWeight.bold, color: Color(0xFF333333)),
+            ),
+            const SizedBox(height: 16),
+            Row(
+              children: [
+                Container(
+                  width: 10,
+                  height: 10,
+                  decoration: BoxDecoration(
+                    color: _getStatusColor(status),
+                    shape: BoxShape.circle,
+                  ),
+                ),
+                const SizedBox(width: 8),
+                Container(
+                  padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 4),
+                  decoration: BoxDecoration(
+                    color: _getStatusColor(status).withValues(alpha: 0.12),
+                    borderRadius: BorderRadius.circular(12),
+                  ),
+                  child: Text(
+                    status,
+                    style: TextStyle(
+                      fontSize: 13,
+                      fontWeight: FontWeight.w600,
+                      color: _getStatusColor(status),
+                    ),
+                  ),
+                ),
+              ],
+            ),
+          ],
+        ),
+        actions: [
+          TextButton(
+            onPressed: () => Navigator.pop(ctx),
+            child: const Text('关闭', style: TextStyle(color: Color(0xFF635BFF))),
+          ),
+        ],
+      ),
+    );
+  }
 }
 
 // ============================================================