feat(mcp): add mcp package

[xHeaven]

An MCP server package inspired by Laravel’s implementation, but built the Tempest way.

[brendt]

This looks great. Really the only change I'd like to see in this PR is to mark it as experimental in the docs, just so that we aren't stuck with backwards compatibility for now.

Also; I think it would be really good to have a blog post once it's released that's like a tutorial building something for real with it. I'm happy to finetune and review it, but @xHeaven could you write an outline of some sorts?

[xHeaven]

This looks great. Really the only change I'd like to see in this PR is to mark it as experimental in the docs, just so that we aren't stuck with backwards compatibility for now.

Sending a followup in a minute.

Also; I think it would be really good to have a blog post once it's released that's like a tutorial building something for real with it. I'm happy to finetune and review it, but @xHeaven could you write an outline of some sorts?

Totally, I think I can put something together.

[xHeaven]

I'm going to attempt rebasing this thing, let's hope something blows up. Wish me luck.
Okay, that went smoothly.

[staabm]

Okay, that went smoothly.

yay, PHPStan result cache seems to work now