Update current React, Node, Web3 Market project

Hello
The current marketplace is built with React, Node.js, and Solidity smart contracts. It runs, but it is showing its age, and I now need a full-spectrum refresh.

User Interface
• I want the layout redesigned to match our new brand guide, while staying fully responsive from mobile up to 4K screens.
• Several small but important UX features are missing—filters, wallet status banners, and activity toasts all need to be added.
• All work should stay inside our existing React component system (Material-UI v5) so maintenance remains simple.

Backend Logic
• The Node/Express API must be checked for performance bottlenecks and tuned; average response times should land below 150 ms under load.
• Known bugs—chiefly pagination glitches and duplicate order creation—must be resolved.
• New endpoints are required for bulk listing management and off-chain metadata caching.

Smart Contracts
• Contracts are already audited but need minor logic upgrades to support the new bulk-listing flow and an adjustable marketplace fee.
• Gas efficiency is important; aim for measurable savings where possible.
• All changes should be unit-tested with Hardhat and verified on Etherscan after deployment.

Acceptance Criteria
1. Redesigned UI passes Lighthouse accessibility and performance scores ≥90.
2. Backend load test (Artillery) sustains 500 rps with error rate <0.1 %.
3. Updated contracts compile, test, and deploy on Goerli and mainnet with identical bytecode verification.
4. End-to-end Cypress suite runs green.

Code lives in a private GitHub repo; branch protection and PR reviews are already configured. Continuous deployment uses GitHub Actions → Vercel for the front end and → Heroku for the API; updates must integrate cleanly into that pipeline.

If questions arise, ping me in the repo discussion and I’ll respond promptly so we can keep momentum.

Thank you