Move the wave 1 phase 7 batch (fireworks_ai, gemini, gigachat, github_copilot; 20 files) from tests/test_litellm to tests/unit after judging every test function under a behaviour mutation. Seven wiring or mock-echo tests that stayed green are deleted. The fireworks cost calculator tests get a local model_cost save/restore fixture since the tests/unit tree has no shared conftest for it
Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>