chore: ignore non-default venv directory names

Add venv/, env/, and *-env/ so virtualenvs created under names other
than .venv (e.g. the gradio-env/ seen earlier) cannot be accidentally
committed.

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

.gitignore

@@ -2,6 +2,9 @@
 __pycache__/
 *.pyc
 .venv/
+venv/
+env/
+*-env/
 uv.lock
 
 # Testing