Migrate to Next.js and Resolve Build Warnings

[Maricaya]

Switch the project setup from Create React App to Next.js to improve build performance and address existing console warnings.

Steps

• [ ] Replace create-react-app with Next.js, optimizing the build and loading speeds.
• [ ] Resolve all console warnings for a cleaner output.
• [ ] Verify that all current functionality remains intact after the migration.

Note Currently preparing for an exam, so work on this task will start later.