fix: tighten schema definition types

[danielroe]

🔗 Linked issue

nuxt/nuxt#22340

❓ Type of change

• 📖 Documentation (updates to the documentation, readme, or JSdoc annotations)
• 🐞 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)
• 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

We currently have an issue with newer typescript versions whereby $resolve (and similar 'magic' keys) are not being typed correctly because they could also be equally well typed with any. This makes a change to SchemaDefinition types that removes the any signature in favour of explicit JSValue types (but only for keys that do not match $resolve, etc.).

This increases type safety and may result in an error when an unknown property is assigned to a schema value. But nevertheless this is worth testing to ensure no (unintended) regressions.

📝 Checklist

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

[danielroe]

FYI: these were the changes necessary to get migrate Nuxt to the new definition: nuxt/nuxt@6604ed7.

I don't believe these were the result specifically of this change but due to greater strictness in latest TS version.

As well as the changes in this PR, I would suggest we also relax the InputObject types when used within applyDefaults and resolveSchema - ie. at the moment it is asserting that the input object must have a key signature, but I think we should not do so.

[codecov]

Codecov Report

Merging #102 (a17175e) into main (347c312) will not change coverage.
The diff coverage is 100.00%.

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##             main     #102   +/-   ##
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  Coverage   88.00%   88.00%           
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  Files           8        8           
  Lines        1167     1167           
  Branches      270      270           
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  Hits         1027     1027           
  Misses        140      140           

Files Changed	Coverage Δ
src/types.ts	100.00% <100.00%> (ø)