feat(lagon): write Lagon config on build

[QuiiBz]

🔗 Linked issue

#966

❓ Type of change

• 📖 Documentation (updates to the documentation or readme)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality like performance)
• ✨ New feature (a non-breaking change that adds functionality)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

Since @lagon/cli@0.5.0, Lagon supports configuration files (https://github.com/lagonapp/lagon/releases/tag/%40lagon%2Fcli%400.5.0)

This PR outputs Lagon's configuration file when the build is complete. It's written inside ${output.dir}/.lagon/config.json (e.g .output/.lagon/config.json) and allows to start the dev server / deploy the function without specifying the function's entry point (server/index.mjs) and the public directory (public) manually.

Notes:

• Fields are written in snake_case
• All paths are relative to the parent of the .lagon folder
• function_id & organization_id fields are empty, they are used to detect if the function has been deployed or not
• client field is a path to a client-side JS script that can be bundled and injected into the assets, but is useless for Nitro.

📝 Checklist

• I have linked an issue or discussion.
• I have updated the documentation accordingly.

[codecov]

Codecov Report

Merging #996 (0d27b76) into main (d83f2b6) will decrease coverage by 0.10%.
The diff coverage is 39.39%.

@@            Coverage Diff             @@
##             main     #996      +/-   ##
==========================================
- Coverage   67.79%   67.70%   -0.10%     
==========================================
  Files          60       60              
  Lines        6133     6162      +29     
  Branches      692      694       +2     
==========================================
+ Hits         4158     4172      +14     
- Misses       1966     1981      +15     
  Partials        9        9              

Impacted Files	Coverage Δ
src/presets/lagon.ts	35.71% <39.39%> (+4.76%)	⬆️
src/rollup/plugins/esbuild.ts	54.41% <0.00%> (+1.07%)	⬆️

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[pi0]

Thanks for the pull request. I have added some basic types for config.

BTW even though the .lagon/config.json is generated, I get a warning like this: (CLI version 0.5.2)

Will try to compile CLI locally and debug later.