Add AGENTS.md support

[calejvaldez]

Summary

Implementing an AGENTS.md file in the root of the repository so that AI agents can use that file to help developers.

Reasoning

VS Code recently implemented support for AGENTS.md files. Seeing as how AI, and specifically AI agents, are being used more and more by developers, I believe it is fair for this to be implemented.

Important

This is not meant to encourage vibe coding. Iris software handles critical data, so vibe coding should be considered off limits in this repository.

[calejvaldez]

Some of the things I'd want in the AGENTS.md file:

• Basic project setup instructions
• pnpm commands
• code style guidelines

Probably some more stuff as well.