chore: apply ruff auto-fixes and remove dead AST scripts

gemini.py

@@ -1,10 +1,8 @@
 # gemini.py
 from __future__ import annotations
 import tomllib
-from pathlib import Path
 from typing import Any
 from google import genai
-from google.genai import types
 
 _client: genai.Client | None = None
 _chat: Any = None