Pre-import api, config, and lovelace in bootstrap to avoid loading th…

…em at runtime (#111752)

homeassistant/bootstrap.py

@@ -21,7 +21,18 @@
 import yarl
 
 from . import config as conf_util, config_entries, core, loader, requirements
-from .components import http
+
+# Pre-import config and lovelace which have no requirements here to avoid
+# loading them at run time and blocking the event loop. We do this ahead
+# of time so that we do not have to flag frontends deps with `import_executor`
+# as it would create a thundering heard of executor jobs trying to import
+# frontend deps at the same time.
+from .components import (
+    api as api_pre_import,  # noqa: F401
+    config as config_pre_import,  # noqa: F401
+    http,
+    lovelace as lovelace_pre_import,  # noqa: F401
+)
 from .const import (
     FORMAT_DATETIME,
     KEY_DATA_LOGGING as DATA_LOGGING,