chore: add .nvmrc for consistent Node versioning

[srinidhi-2006-bit]

Summary

Added an .nvmrc file to define a consistent Node.js version for contributors and development environments.

Closes #993

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Type of Change

• Bug fix
• New feature
• Documentation / Developer Experience improvement
• Refactor / code cleanup

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Changes Made

• Added .nvmrc file at the repository root
• Specified Node.js version 20
• Improved environment consistency across contributors
• Simplified project setup for developers using NVM

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How to Test

1. Ensure .nvmrc exists in the repository root
2. Run:

nvm use

3. Verify the correct Node.js version is selected
4. Run the project normally and confirm everything works as expected

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Screenshots (if UI change)

N/A

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Checklist

• Linked issue in summary
• Self-reviewed the diff
• No breaking changes introduced
• Added only the required configuration file
• Added/updated tests if applicable

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Additional Notes

Adding .nvmrc helps contributors use a consistent Node.js version, reducing setup issues and environment-related bugs.

[vercel]

@srinidhi-2006-bit is attempting to deploy a commit to the PRIYANSHU DOSHI's projects Team on Vercel.

A member of the Team first needs to authorize it.

[github-actions]

GSSoC Label Checklist 🏷️

@Priyanshu-byte-coder — please apply the appropriate labels before merging:

Difficulty (pick one):

• level:beginner — 20 pts
• level:intermediate — 35 pts
• level:advanced — 55 pts
• level:critical — 80 pts

Quality (optional):

• quality:clean — ×1.2 multiplier
• quality:exceptional — ×1.5 multiplier

Validation (required to score):

• gssoc:approved — counts for points
• gssoc:invalid / gssoc:spam / gssoc:ai-slop — does not score

Type labels (type:*) are auto-detected from files and title. Review and adjust if needed.
Points formula: (difficulty × quality_multiplier) + type_bonus

[srinidhi-2006-bit]

Hi @Priyanshu-byte-coder,

I've completed the requested changes and submitted the PR for review. When you review it, could you please add the gssoc:approved label before merging if everything looks good?

Thank you for your time and feedback!