test: 隔离单测中的站点原生资源 (#6452)

* test: isolate native site resources

* refactor(test): retain sites stub helper contract

* fix(test): preserve sites stub probe imports

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Co-authored-by: jxxghp <jxxghp@gmail.com>

scripts/startup/performance.py

@@ -43,9 +43,9 @@ import json
 import sys
 import time
 
-from app.testing.bootstrap import install_sites_stub
+from app.testing.bootstrap import ensure_sites_stub
 
-install_sites_stub()
+ensure_sites_stub()
 before = set(sys.modules)
 started_at = time.perf_counter()
 importlib.import_module({target!r})
@@ -100,9 +100,9 @@ import time
 
 from fastapi import FastAPI
 
-from app.testing.bootstrap import install_sites_stub
+from app.testing.bootstrap import ensure_sites_stub
 
-install_sites_stub()
+ensure_sites_stub()
 from app.startup import lifecycle