fix: 前端表格行类型断言修复并补充 psycopg-pool 依赖

- 审批/项目/租户/用户设置等视图新增 asXxx 类型断言辅助函数
- search-fields 由字符串改为数组传参
- backend 依赖新增 psycopg-pool，Dockerfile 依赖校验同步更新

backend/pyproject.toml

@@ -10,6 +10,7 @@ dependencies = [
   "pydantic>=2.7.0",
   "sqlalchemy>=2.0.30",
   "psycopg[binary]>=3.2.1",
+  "psycopg-pool>=3.2.1",
   "alembic>=1.13.1",
   "redis>=5.0.4",
   "httpx>=0.27.0",

backend/requirements.txt

@@ -4,6 +4,7 @@ python-multipart>=0.0.9
 pydantic>=2.7.0
 sqlalchemy>=2.0.30
 psycopg[binary]>=3.2.1
+psycopg-pool>=3.2.1
 alembic>=1.13.1
 redis>=5.0.4
 httpx>=0.27.0