fix(health): 趋势图数据不显示 — 后端 DTO 元组→结构体 + 前端解包修复

- 后端 IndicatorTimeseriesResp.data 从 Vec<(NaiveDate, f64)> 改为 Vec<DataPoint>
  解决 JSON 序列化为数组而非对象导致前端无法识别的问题
- 前端 VitalSignsChart 正确解包 API 返回的 { indicator, data } 响应结构
- 移除趋势图无用的指标下拉选择器，固定显示收缩压(晨)趋势
- 修复 PatientDetail Card body padding 三层嵌套空白问题

crates/erp-health/src/dto/health_data_dto.rs

@@ -192,7 +192,7 @@ pub struct TrendResp {
 #[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
 pub struct IndicatorTimeseriesResp {
     pub indicator: String,
-    pub data: Vec<(NaiveDate, f64)>,
+    pub data: Vec<DataPoint>,
 }
 
 // ---------------------------------------------------------------------------

crates/erp-health/src/service/trend_service.rs

@@ -214,7 +214,7 @@ pub async fn get_indicator_timeseries(
         .all(&state.db)
         .await?;
 
-    let data: Vec<(chrono::NaiveDate, f64)> = vitals.into_iter().filter_map(|v| {
+    let data: Vec<DataPoint> = vitals.into_iter().filter_map(|v| {
         let val = match indicator.as_str() {
             "heart_rate" => v.heart_rate.map(|x| x as f64),
             "weight" => v.weight.map(|d| d.to_f64().unwrap_or(0.0)),
@@ -225,7 +225,10 @@ pub async fn get_indicator_timeseries(
             "diastolic_bp_evening" => v.diastolic_bp_evening.map(|x| x as f64),
             _ => None,
         };
-        val.map(|fv| (v.record_date, fv))
+        val.map(|fv| DataPoint {
+            date: v.record_date.to_string(),
+            value: fv,
+        })
     }).collect();
 
     Ok(IndicatorTimeseriesResp { indicator, data })
@@ -393,15 +396,8 @@ pub async fn get_mini_trend(
     )
     .await?;
 
-    // 4. 转换为 DataPoint 格式
-    let data_points = timeseries
-        .data
-        .into_iter()
-        .map(|(date, value)| DataPoint {
-            date: date.to_string(),
-            value,
-        })
-        .collect();
+    // 4. 直接使用 DataPoint
+    let data_points = timeseries.data;
 
     Ok(MiniTrendResp {
         indicator,