chore: add gitignore for skill scripts

skills/excalidraw-diagram-generator/SKILL.md

@@ -594,6 +594,7 @@ See bundled references for:
 - `templates/mindmap-template.json` - Mind map starter
 - `scripts/split-excalidraw-library.py` - Tool to split `.excalidrawlib` files
 - `scripts/README.md` - Documentation for library tools
+- `scripts/.gitignore` - Prevents local Python artifacts from being committed
 
 ## Limitations
 

skills/excalidraw-diagram-generator/scripts/.gitignore

@@ -0,0 +1,34 @@
+# Avoid accidentally committing local Python artifacts produced when running these scripts.
+
+# Byte-compiled / cache files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# Virtual environments (people often create these next to scripts)
+.venv/
+venv/
+env/
+ENV/
+
+# Tool caches
+.pytest_cache/
+.mypy_cache/
+.ruff_cache/
+.tox/
+.nox/
+
+# Coverage outputs
+.coverage
+.coverage.*
+htmlcov/
+
+# Packaging/build outputs (rare here, but harmless)
+build/
+dist/
+*.egg-info/
+.eggs/
+
+# OS cruft
+.DS_Store
+Thumbs.db