Apply suggestions from code review

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

test/test_normalize_fqn.py

@@ -1,6 +1,6 @@
 """Unit tests for FQN normalization (no GPU / distributed required)."""
 
-import pytest
+
 from optimizer.core import default_is_muon, is_expert_param, normalize_fqn
 from optimizer.qk_clip import parse_qk_layer