feat(auth)!: migrate customer metadata auth

Remove local auth and user-management endpoints in favor of Keycloak-backed metadata users, project context, admin metadata APIs, and agent auth context.

app/api/v1/router.py

@@ -1,6 +1,7 @@
 from fastapi import APIRouter
 from app.api.v1.endpoints import (
-    auth,
+    admin_metadata,
+    agent_auth,
     project,
     simulation,
     scada,
@@ -15,7 +16,6 @@ from app.api.v1.endpoints import (
     leakage,
     burst_detection,
     burst_location,
-    user_management,  # 新增：用户管理
     audit,  # 新增：审计日志
     meta,
     web_search,
@@ -54,10 +54,10 @@ from app.api.v1.endpoints.timeseries import (
 api_router = APIRouter()
 
 # Core Services
-api_router.include_router(auth.router, prefix="/auth", tags=["Auth"])
+api_router.include_router(agent_auth.router, tags=["Agent Auth"])
 api_router.include_router(
-    user_management.router, prefix="/users", tags=["User Management"]
-)  # 新增
+    admin_metadata.router, prefix="/admin", tags=["Metadata Admin"]
+)
 api_router.include_router(audit.router, prefix="/audit", tags=["Audit Logs"])  # 新增
 api_router.include_router(meta.router, tags=["Metadata"])
 api_router.include_router(project.router, tags=["Project"])