fix: make check-links script cross-platform

[Osaid2993]

Description

This PR fixes 'npm run check-links' so it actually works on Mac, Linux, and the dev container

The script was using 'SET' to define an environment variable, which is Windows-only. On Unix-like systems it just fails immediately with 'SET: not found', the build never even starts.

Type of change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

I tested this by running:

npm run check-links

After the fix, the script runs correctly and reaches the link-validation stage of the build. The remaining failure is from existing invalid hash links like '/api/geometry/#rectangle-around', not from the 'check-links' script itself.

Checklist

If involving code

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• My changes generate no new warnings

If modified config files

• I have checked the following files for changes:
  • package.json

Folders and Files Added/Modified

• Modified:
  • package.json

Additional Notes

This PR is intentionally limited to package.json so the cross-platform script fix stays separate from the repository’s existing build and link validation issues.

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[anandika-nair]

Hi, I reviewed your PR and it looks good overall.

• The issue with the script being Windows-only is clearly explained
• The fix using a cross-platform approach makes sense and improves compatibility for macOS, Linux, and the dev container
• I also like that the PR is kept focused only on the package.json change

I noticed the checks are failing, but it seems related to existing build or link issues rather than this specific change.

One small suggestion:

• It might be helpful to briefly mention in the code or comments what the new script is doing, so it is easier for future contributors to understand.

Overall, this is a clean and useful fix. Good work!