style(core): move Path import to TYPE_CHECKING block in types.py

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

core/types.py

@@ -3,7 +3,10 @@
 from __future__ import annotations
 
 from dataclasses import dataclass, field
-from pathlib import Path as _Path
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from pathlib import Path as _Path
 
 
 @dataclass(frozen=True)