Front end migration to only react

[SaboniAmine]

Description

This PR introduces a refactoring of the front end app, with following changes :

• Removing next.js app and replacing by a lightweight pure react version (build size went from 400 MB to 1.2 MB), with vite bundling
• Factorizing all design tokens under the tailwind config
• adding Zod runtime validation for API exchanges
• remove periodic polling and replace by revalidate on focus or manual refresh with additional buttons
• added accessibility labels

Related Issue

Please link to the issue this PR resolves: [issue #]

Motivation and Context

Why is this change required? What problem does it solve?

How Has This Been Tested?

Please describe in detail how you tested your changes.

Screenshots (if appropriate):

Types of changes

What types of changes does your code introduce? Put an x in all the boxes that apply:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

Go over all the following points, and put an x in all the boxes that apply.

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING.md document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.92%. Comparing base (a88000f) to head (ef75c4f).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1076      +/-   ##
==========================================
- Coverage   88.94%   88.92%   -0.03%     
==========================================
  Files          45       45              
  Lines        4306     4306              
==========================================
- Hits         3830     3829       -1     
- Misses        476      477       +1     

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[inimaz]

LGTM, tested offline