code-to10 v6 A14 batch2: test E402/F401 cleanup plus touched-file residual E,F cleanup

(cherry picked from commit 1db02545f74c96b3b92be4fc32954659cec1f814)

Reconcile-conflict: A14b E402 imports referencing cloud.handler_core (does not exist here; core methods live in server.py) — kept HEAD imports with incoming's noqa: E402 markers, dropped the unused core_mod import (verified unused elsewhere in both files).

cloud/tests/test_v2cov_worker_deliver.py

@@ -36,9 +36,9 @@ from unittest import mock
 REPO_ROOT = Path(__file__).resolve().parents[2]
 sys.path.insert(0, str(REPO_ROOT))
 
-from cloud.server import init_db
-from cloud.todos import create_todo as _create_todo
-from cloud.worker import Worker
+from cloud.server import init_db  # noqa: E402
+from cloud.todos import create_todo as _create_todo  # noqa: E402
+from cloud.worker import Worker  # noqa: E402
 
 FAKE_ENV = {"XCM_API_KEY": "test-placeholder"}
 
@@ -283,7 +283,6 @@ class ControlFallbackTestCase(DeliverBase):
     def test_retry_not_done_when_rowcount_zero(self):
         self._insert("E1", status="failed", parent="PM")
         worker = self._worker()
-        real_connect = sqlite3.connect
 
         class _CursorProxy:
             def __init__(self, real):