feat: Iteration 3 — 咨询轮询、统计概览、埋点后端

- consultation_service 支持 after_id 增量消息查询
- 小程序咨询详情页 8 秒轮询新消息
- 新增 DashboardStatsResp 综合统计端点 (/statistics/dashboard)
- 新增 /analytics/batch 埋点接收端点（日志记录模式）

crates/erp-health/src/handler/stats_handler.rs

@@ -46,3 +46,22 @@ where
     let result = stats_service::get_follow_up_statistics(&state, ctx.tenant_id).await?;
     Ok(Json(ApiResponse::ok(result)))
 }
+
+pub async fn get_dashboard_stats<S>(
+    State(state): State<HealthState>,
+    Extension(ctx): Extension<TenantContext>,
+) -> Result<Json<ApiResponse<DashboardStatsResp>>, AppError>
+where
+    HealthState: FromRef<S>,
+    S: Clone + Send + Sync + 'static,
+{
+    require_permission(&ctx, "health.patient.list")?;
+    let patients = stats_service::get_patient_statistics(&state, ctx.tenant_id).await?;
+    let consultations = stats_service::get_consultation_statistics(&state, ctx.tenant_id).await?;
+    let follow_ups = stats_service::get_follow_up_statistics(&state, ctx.tenant_id).await?;
+    Ok(Json(ApiResponse::ok(DashboardStatsResp {
+        patients,
+        consultations,
+        follow_ups,
+    })))
+}