Tie install model scope to request scope

This is probably the more general fix for
#18627.

lib/galaxy/web/framework/base.py

@@ -171,9 +171,11 @@ def __call__(self, environ, start_response):
 
         try:
             self._model.set_request_id(request_id)  # Start SQLAlchemy session scope
+            self._install_model.set_request_id(request_id)
             return self.handle_request(request_id, path_info, environ, start_response)
         finally:
             self._model.unset_request_id(request_id)  # End SQLAlchemy session scope
+            self._install_model.unset_request_id(request_id)  # End SQLAlchemy session scope
             self.trace(message="Handle request finished")
             if self.trace_logger:
                 self.trace_logger.context_remove("request_id")

lib/galaxy/webapps/base/webapp.py

@@ -121,6 +121,7 @@ def __init__(
         # We need this to set the REQUEST_ID contextvar in model.base *BEFORE* a GalaxyWebTransaction is created.
         # This will ensure a SQLAlchemy session is request-scoped for legacy (non-fastapi) endpoints.
         self._model = galaxy_app.model
+        self._install_model = getattr(galaxy_app, "install_model", None)
 
     def build_apispec(self):
         """

lib/galaxy/webapps/galaxy/api/__init__.py

@@ -98,10 +98,12 @@ async def get_app_with_request_session() -> AsyncGenerator[StructuredApp, None]:
     app = get_app()
     request_id = request_context.data["X-Request-ID"]
     app.model.set_request_id(request_id)
+    app.install_model.set_request_id(request_id)
     try:
         yield app
     finally:
         app.model.unset_request_id(request_id)
+        app.install_model.unset_request_id(request_id)
 
 
 DependsOnApp = cast(StructuredApp, Depends(get_app_with_request_session))