chore: configure gitignore

.gitignore

@@ -1 +1,45 @@
 HANDOFF.md
+.claude/HANDOFF.md
+
+# Python
+__pycache__/
+*.py[cod]
+*.pyo
+.venv/
+venv/
+*.egg-info/
+dist/
+.pytest_cache/
+.mypy_cache/
+.ruff_cache/
+
+# Environment
+.env
+*.env.local
+
+# Database
+backend/data/*.db
+backend/data/*.db-shm
+backend/data/*.db-wal
+
+# Alembic
+backend/alembic/versions/*.pyc
+
+# Node
+frontend/node_modules/
+frontend/dist/
+frontend/.vite/
+
+# PWA
+frontend/public/sw.js
+frontend/public/workbox-*.js
+frontend/public/sw.js.map
+
+# OS
+.DS_Store
+Thumbs.db
+
+# IDE
+.vscode/
+.idea/
+*.swp