feat: Add development scripts for environment check and service management

- check-env.sh: Validates Python 3.10+, Node.js, Docker, venv, .env, ports
- start-dev.sh: Starts MinIO, backend, frontend with health checks
- stop-dev.sh: Gracefully stops all services

Scripts are placed in project root for easy access.
Supports --help flag and colored output.

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

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

.gitignore

@@ -34,3 +34,7 @@ server.log
 node_modules/
 frontend/dist/
 frontend/.vite/
+
+# Development scripts
+.pids/
+logs/