fix(health): 设备数据管线 Phase 1 缺陷修复 + AI 产品策略讨论

- device_readings 批量插入添加 ON CONFLICT 去重唯一索引
- 小程序 BLEManager 增加离线缓存（Storage 持久化 + 启动重传）
- 新增 device_readings 90 天数据保留清理定时任务
- 小米手环适配器增加 RACP 历史心率读取支持
- SSE 告警按医生过滤已确认实现（patient_doctor_relation）
- 新增 AI 产品策略与设备数据医院场景讨论记录

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

@@ -223,13 +223,26 @@ async fn batch_insert_readings(
         })
         .collect();
 
-    let count = models.len() as u64;
+    let total = models.len() as u64;
     device_readings::Entity::insert_many(models)
+        .on_conflict(
+            sea_orm::sea_query::OnConflict::columns([
+                device_readings::Column::TenantId,
+                device_readings::Column::PatientId,
+                device_readings::Column::DeviceId,
+                device_readings::Column::Metric,
+                device_readings::Column::MeasuredAt,
+            ])
+            .do_nothing()
+            .to_owned(),
+        )
         .exec(db)
         .await
         .map_err(|e| HealthError::DbError(e.to_string()))?;
 
-    Ok(count)
+    // ON CONFLICT DO NOTHING 不返回精确插入数，返回提交总数
+    // 调用方通过 BatchResult.duplicates 字段语义不变
+    Ok(total)
 }
 
 async fn upsert_hourly_aggregates(
@@ -532,3 +545,33 @@ async fn sync_bp_glucose_to_vital_signs(
 
     Ok(())
 }
+
+/// 清理超过 90 天的设备原始数据，分批删除避免长事务
+pub async fn cleanup_stale_readings(
+    db: &DatabaseConnection,
+) -> HealthResult<u64> {
+    let cutoff = Utc::now() - chrono::Duration::days(90);
+    let batch_size = 1000i64;
+    let mut total_deleted = 0u64;
+
+    loop {
+        let result = db.execute(sea_orm::Statement::from_sql_and_values(
+            sea_orm::DatabaseBackend::Postgres,
+            "DELETE FROM device_readings WHERE measured_at < $1 AND id IN (SELECT id FROM device_readings WHERE measured_at < $1 LIMIT $2)",
+            [cutoff.into(), (batch_size as i32).into()],
+        )).await;
+
+        match result {
+            Ok(res) => {
+                let rows = res.rows_affected();
+                total_deleted += rows;
+                if rows < batch_size as u64 {
+                    break;
+                }
+            }
+            Err(e) => return Err(HealthError::DbError(e.to_string())),
+        }
+    }
+
+    Ok(total_deleted)
+}