docs: sync README test counts (58 fast / 68 total)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

README.md

@@ -39,6 +39,6 @@ The Gradio interface launches at `http://localhost:7860`.
 uv run ruff check .             # lint
 uv run ruff format .            # format
 uv run ty check                 # type check
-uv run pytest -m "not slow"     # 51 fast tests
-uv run pytest                   # all 61 tests (slow require CUDA + model download)
+uv run pytest -m "not slow"     # 58 fast tests
+uv run pytest                   # all 68 tests (slow require CUDA + model download)
 ```