Document GitHub Copilot Instructions for React Development

[pplancq]

Type of Pull Request:

• Bug fix
• New feature
• Documentation
• Other (specify):

Associated Issue:
Closes #194

Context:
This PR addresses the need for clear, actionable documentation on using GitHub Copilot within the React codebase. It fulfills the requirements outlined in issue #194, ensuring contributors have guidance on enabling Copilot, usage tips, coding standards, accessibility and performance guidelines, and repository-specific recommendations. The documentation is written in English and linked from the main README or relevant documentation for easy access.

Proposed Changes:

• Added comprehensive instructions for enabling and using GitHub Copilot in the React codebase
• Included usage tips, coding standards, accessibility (WCAG/RGAA) and performance optimization guidelines
• Linked documentation from the main README and relevant sections for discoverability
• Ensured all instructions are in English and up to date

Checklist:

• I have verified that my changes work as expected
• I have updated the documentation if necessary
• I have thought to rebase my branch
• I have applied the correct label according to the type of PR (bug/feature/documentation)

Additional Information:
None

[lbroudoux]

Thanks @pplancq for pushing this one! I have one minor change request regarding the Git commit instructions, specifically related to mandatory signing. Thanks a ton!

[lbroudoux]

LGTM