feat(ai): 实现 AI 数据桥接 — 4 个 HealthDataProvider 方法从 stub 替换为真实查询

- get_lab_report: 查询 lab_report + patient，解析 JSON items 构造 LabReportDto
- get_vital_signs: 查询 vital_signs 时间序列，按指标提取 8 种体征数据
- get_patient_summary: 聚合 patient + diagnosis + medication_record + health_record
- get_full_report: 查询 health_record + 关联诊断和化验报告构造章节
- AiState 新增 health_provider 字段，erp-server 注入 HealthDataProviderImpl
- 4 个 SSE handler 从 placeholder JSON 改为调用 provider + sanitizer 真实数据流

crates/erp-ai/src/state.rs

@@ -1,6 +1,7 @@
 use std::sync::Arc;
 
 use erp_core::events::EventBus;
+use erp_core::health_provider::HealthDataProvider;
 use sea_orm::DatabaseConnection;
 
 use crate::service::analysis::AnalysisService;
@@ -14,4 +15,5 @@ pub struct AiState {
     pub analysis: Arc<AnalysisService>,
     pub prompt: Arc<PromptService>,
     pub usage: Arc<UsageService>,
+    pub health_provider: Arc<dyn HealthDataProvider>,
 }