Wishlist: import Optional (fix ruff F821 in processing.py)

make_wishlist_batch_row / _run_wishlist_cycle annotate params with Optional,
but the typing import only had Any/Callable/Dict. Slipped past py_compile +
tests because 'from __future__ import annotations' makes annotations strings
(never evaluated at runtime), but ruff flags it statically (F821).

core/wishlist/processing.py

@@ -7,7 +7,7 @@ from dataclasses import dataclass
 from datetime import datetime
 from contextlib import AbstractContextManager
 from types import SimpleNamespace
-from typing import Any, Callable, Dict
+from typing import Any, Callable, Dict, Optional
 
 from core.wishlist.payloads import build_failed_track_wishlist_context
 from core.wishlist.selection import filter_wishlist_tracks_by_category, sanitize_and_dedupe_wishlist_tracks