```

feat: 添加数据库迁移脚本并更新Dockerfile配置

- 在Dockerfile中添加alembic配置文件和目录的复制指令
- 更新alembic/env.py注册新的模块模型：events、workflows、writebacks
- 生成完整的初始数据库schema迁移脚本，包含以下表：
  - approval_requests, attendance_records, audit_logs, domain_events
  - expenses, feishu_event_receipts, fund_accounts, legacy_sync_runs
  - official_writeback_runs, performance_metrics, policies, procurements
  - projects, report_push_runs, risk_event_actions, risk_events
  - standards, suppliers, work_reports, work_tasks, workflow_actions
  - workflow_instances等21个数据表结构定义
- 在API路由器中添加新模块的路由：events、workflows、writebacks、observability
```

app/modules/observability/routes.py

@@ -0,0 +1,30 @@
+from fastapi import APIRouter, Depends
+from sqlalchemy.orm import Session
+
+from app.core.database import get_db
+from app.core.security import require_api_key
+from app.modules.observability.service import ObservabilityService
+
+router = APIRouter()
+
+
+@router.get("/health/live")
+def live(
+    db: Session = Depends(get_db),
+) -> dict:
+    _ = db
+    return ObservabilityService(db).live()
+
+
+@router.get("/health/ready")
+def ready(
+    db: Session = Depends(get_db),
+) -> dict:
+    return ObservabilityService(db).ready()
+
+
+@router.get("/metrics", dependencies=[Depends(require_api_key)])
+def metrics(
+    db: Session = Depends(get_db),
+) -> dict:
+    return ObservabilityService(db).metrics()