fix(tradein/data): dry-run бэкфилла — savepoint-паритет с write-веткой (#2236)

tradein-mvp/backend/scripts/backfill_external_valuations_house_id.py

@@ -165,21 +165,21 @@ def _process_row(
     stats.bump(row.source, "processed")
 
     try:
-        if dry_run:
+        # SAVEPOINT в обеих ветках: даже в dry-run matcher бьёт по БД (SELECT'ы),
+        # и его exception на реальной сессии перевёл бы транзакцию в aborted →
+        # каскад «current transaction is aborted» на всех последующих строках.
+        with db.begin_nested():
             house_id = matcher(db, row.address)
-        else:
+            if house_id is not None and not dry_run:
-            with db.begin_nested():
+                db.execute(
-                house_id = matcher(db, row.address)
+                    text(
-                if house_id is not None:
+                        "UPDATE external_valuations "
-                    db.execute(
+                        "   SET house_id = CAST(:hid AS bigint) "
-                        text(
+                        " WHERE id = CAST(:eid AS bigint) "
-                            "UPDATE external_valuations "
+                        "   AND house_id IS NULL"
-                            "   SET house_id = CAST(:hid AS bigint) "
+                    ),
-                            " WHERE id = CAST(:eid AS bigint) "
+                    {"hid": house_id, "eid": row.id},
-                            "   AND house_id IS NULL"
+                )
-                        ),
-                        {"hid": house_id, "eid": row.id},
-                    )
 
         if house_id is not None:
             stats.resolved += 1