fix #2595 : update Node.js version requirement in README to match package.json

[subhamkumarr]

Fix Node.js version requirement documentation mismatch

Problem

The README.md incorrectly states "Node.js version 18+" while package.json specifies "node": "20.x" in the engines field. This inconsistency can mislead contributors who may install an incompatible Node.js version.

Solution

Updated README.md to specify "Node.js version 20.x" to match the actual requirement in package.json.

Changes

• Updated README.md line 14: Changed "Node.js version 18+" to "Node.js version 20.x"

Testing

• Verified that the change aligns with the package.json engines field
• No code changes, documentation only

Impact

• ✅ Prevents confusion for new contributors
• ✅ Ensures accurate setup instructions
• ✅ Aligns documentation with actual project requirements

Fixes #2595

---

Note

Aligns docs with actual engine requirement.

• Updates README.md prerequisite from Node.js 18+ to Node.js 20.x to match package.json engines.node

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[subhamkumarr]

@AyushBherwani1998 could you please review this and merge it when you get a chance? Thanks!
Issue #2595