feat(create-vite): add AI agent experience (AX) support

[fengmk2]

Integrate @vercel/detect-agent to improve create-vite experience for AI coding agents. When an AI agent is detected in interactive mode, display a concise tip showing how to use non-interactive mode for single-command execution.

This enhancement follows Agent Experience (AX) best practices by providing clear, actionable guidance to AI agents, helping them understand how to scaffold projects without interactive prompts.

fixes #20951

🤖 Generated with Claude Code