chore(tech-debt): Finalize gui_2.py cleanup and test suite discipline

tests/test_token_usage.py

@@ -1,3 +1,4 @@
+import pytest
 import sys
 import os
 
@@ -10,4 +11,4 @@ def test_token_usage_tracking() -> None:
  ai_client.reset_session()
  # Mock an API response with token usage
  # This would test the internal accumulator in ai_client
- pass
+ pytest.fail("TODO: Implement assertions")