Add LikeC4 extension

[Lenivvenil]

Summary

Adds LikeC4 architecture-as-code language support for Zed:

• Tree-sitter grammar — syntax highlighting, bracket matching, auto-indentation, code outline
• LSP integration — official @likec4/language-server providing completions, diagnostics, hover, go-to-definition, find references, and rename
• File detection — .likec4 and .c4 extensions

Extension repo: https://github.com/Lenivvenil/zed-likec4
Grammar repo: https://github.com/Lenivvenil/tree-sitter-likec4

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[Lenivvenil]

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[Lenivvenil]

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[Lenivvenil]

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[MrSubidubi]

Thanks for this!

I very much would like for you to remove https://github.com/Lenivvenil/zed-likec4/blob/c094b7d8d0c213799df843ec1ad58a8c59483385/src/lib.rs#L19-L72 - this should not be needed, as this should be handled by the NPM package install. Can you elaborate on this perhaps?

[Lenivvenil]

Thanks for the review!

The ESM resolve hook is unfortunately necessary because Zed ships Node.js v24, which enforces strict ESM resolution. Without the hook, the server crashes immediately on startup:

Error [ERR_MODULE_NOT_FOUND]: Cannot find module
  '.../node_modules/vscode-languageserver/node'
  imported from '.../node_modules/@likec4/language-server/dist/bundled.mjs'
Did you mean to import "vscode-languageserver/node.js"?

Root cause: @likec4/language-server is an ESM package ("type": "module") that imports vscode-languageserver/node (without .js extension). vscode-languageserver@9.0.1 is a CJS package with no exports field in its package.json. Node v24 requires explicit .js extensions for subpath imports of such packages — this is an upstream issue in vscode-languageserver.

The hook does two things:

1. Retries failed imports with .js suffix — fixes the ERR_MODULE_NOT_FOUND for vscode-languageserver/node → vscode-languageserver/node.js
2. Stubs optional peer deps (bundle-require, esbuild) — these are statically imported by @likec4/language-server but only used for loading likec4.config.ts files, not for LSP operations. zed::npm_install_package does not install peer dependencies.

I verified this on macOS with the exact Node binary Zed bundles (node-v24.11.0-darwin-arm64). The server cannot start without the hook.

Once vscode-languageserver ships an exports field (or @likec4/language-server switches to explicit .js imports), the hook can be removed.