chore: improve .gitignore with better organization and macOS exclusion

Add section comments for better organization and exclude .DS_store files created by macOS Finder.

Changes:
- Add "# Python" section header for Python-related ignores
- Add "# Mac Os" section and .DS_store exclusion
- Fix missing newline at end of file

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: vincentbergman

.gitignore

@@ -1,8 +1,12 @@
+# Python
 .venv/
 .pytest_cache/
 __pycache__/
 dist/
 logs/
 data/
 
-*.pyc
+*.pyc
+
+# Mac Os
+.DS_store