Add CLAUDE.md for LLM agent assistance

[andyw8]

Inspired by Shopify/ruby-lsp#3668

This is exactly as generated by /init.

[st0012]

While /init usually does a good job getting the overview, it still makes quite a bit of mistakes. Can you actually review the content and verify that everything it says is correct AND necessary?

[andyw8]

While /init usually does a good job getting the overview, it still makes quite a bit of mistakes. Can you actually review the content and verify that everything it says is correct AND necessary?

Oops, I had meant to open as a draft PR. I've pushed some updates.

[vinistock]

Let's add a symlink for .github/copilot-instructions.md, similar to what we did in the LSP.

Also, I think it might be worth going into a bit more detail about the architecture. For example, how the add-on communicates with the runtime and what's the responsibility of each side

[andyw8]

Also, I think it might be worth going into a bit more detail about the architecture. For example, how the add-on communicates with the runtime and what's the responsibility of each side

I think it may be better to add that when actually working on a feature, to allow for experimentation and iteration. WDYT?