Add .gitignore to exclude Python cache files

Excludes:
- __pycache__/ directories
- *.pyc, *.pyo, *.pyd files
- Virtual environments
- IDE files
- Environment variables
- Test artifacts
- Database files
- Node modules
- Temporary files

This prevents Python bytecode cache files from being tracked in git.

.gitignore

@@ -0,0 +1,68 @@
+# Python
+__pycache__/
+*.py[cod]
+*$py.class
+*.so
+.Python
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+
+# Virtual environments
+venv/
+ENV/
+env/
+.venv
+
+# IDE
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+.DS_Store
+
+# Testing
+.pytest_cache/
+.coverage
+htmlcov/
+.tox/
+
+# Environment variables
+.env
+.env.local
+.env.*.local
+
+# Logs
+*.log
+
+# Database
+*.db
+*.sqlite
+*.sqlite3
+
+# Node
+node_modules/
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+
+# Railway
+.railway/
+
+# Temporary files
+*.tmp
+*.temp
+.cache/