code-to10 v7 mech merge fix: SqliteScorecardGainLedger uses cloud.db.connect instead of sqlite3.connect (arch conformance layer rule), no semantics changed

(cherry picked from commit bde36a84880574c2297aaee9ed08312cd0e2c0fc)

cloud/scorecard_diff.py

@@ -90,6 +90,8 @@ from __future__ import annotations
 
 import sqlite3
 
+from cloud.db import connect as _db_connect
+
 TABLES = ("code", "production", "product")
 
 # 停表阈值：测试默认值、未拍板。生产阈值须用户拍板后显式传入。
@@ -297,8 +299,9 @@ class SqliteScorecardGainLedger:
             self._conn = connection
             self._owns_conn = False
         else:
-            self._conn = sqlite3.connect(str(db_path))
-            self._conn.row_factory = sqlite3.Row
+            # 层规则：服务层不得直连驱动，须走 cloud.db.connect
+            # （其 SQLite 路径已设 WAL + busy_timeout + Row）。
+            self._conn = _db_connect(str(db_path))
             self._owns_conn = True
         self._conn.execute(SQLITE_DDL)
         self._conn.commit()