Bounty: Add Documentation for React.js Frontend

[Thanhdn1984]

Summary

• Replace the starter-template README with project documentation for Kleo Connect.
• Add local setup, environment variables, project structure, routes, scripts, build/test/deploy notes, and contribution guidance.

Validation

• npm install attempted, but dependency installation fails on this arm64/Node 22 environment while building node-datachannel (prebuild ERR! build TypeError: expected first argument to be an array).
• README-only change reviewed for Markdown structure and repo paths.

[Thanhdn1984]

Bounty issue: #56

Validation note: this is a README-only documentation update. I attempted local install/validation, but npm install fails on the current arm64/Node 22 runner while building node-datachannel (prebuild ERR! build TypeError: expected first argument to be an array).