Add .gitignore for Node.js/Docker project and CLAUDE.md

- Add comprehensive .gitignore with Node.js patterns
- Exclude .env files and variants
- Add Docker Compose exclusions
- Create CLAUDE.md for repository guidance

.gitignore

@@ -0,0 +1,67 @@
+# Dependencies
+node_modules/
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+pnpm-debug.log*
+lerna-debug.log*
+
+# Environment variables
+.env
+.env.local
+.env.development.local
+.env.test.local
+.env.production.local
+.env*.local
+
+# Build output
+dist/
+build/
+out/
+.next/
+.nuxt/
+.cache/
+.parcel-cache/
+
+# IDE and editor files
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+.DS_Store
+Thumbs.db
+
+# Logs
+logs/
+*.log
+
+# Testing
+coverage/
+.nyc_output/
+
+# TypeScript
+*.tsbuildinfo
+.tsc-cache/
+
+# Package manager files
+.npm/
+.yarn/
+.pnp.*
+.yarn-integrity
+
+# Docker
+.dockerignore
+docker-compose.override.yml
+
+# Miscellaneous
+.eslintcache
+.stylelintcache
+*.pid
+*.seed
+*.pid.lock
+.grunt/
+.lock-wscript
+.node_repl_history
+.npmrc
+.yarnrc