🤖 Add AGENTS.md and copilot-instructions.md during initialization.

[ShayokhShorfuddin]

Hello. I initialized a Tanstack Start project with SolidJS this morning. Opening the project, I saw a file called .cursorrules, which appears to be a file related to Cursor AI IDE, and it's fine. However, the issue is that I use Visual Studio Code, which has AGENTS.md and copilot-instructions.md as equivalents to .cursorrules. I think it would be good to create these 2 (or just the AGENTS.md) files during initialization.