🔨 refactor: Add Cache Busting to index.html

[danny-avila]

Summary

I implemented cache busting for the index.html file to ensure users always receive the latest version of the application. This change addresses potential issues where users might experience outdated content due to browser caching.

• Added three meta tags to the index.html file for cache control:
  • Set 'cache-control' to "no-cache, no-store, must-revalidate"
  • Set 'expires' to '0'
  • Set 'pragma' to 'no-cache'
• These additions prevent browsers from caching the index.html file, ensuring users always load the most recent version of LibreChat

Followup to #3822 as it will more explicitly cache js files based on code changes

Inspired by https://maxtsh.medium.com/the-ultimate-guide-to-cache-busting-for-react-production-applications-d583e4248f02

Change Type

• New feature (non-breaking change which adds functionality)

Testing

To test this change:

1. Deploy the updated index.html file to a test environment
2. Clear your browser cache
3. Load the application and verify it's the latest version
4. Reload the page multiple times to ensure no caching occurs
5. Test on different browsers (Chrome, Firefox, Safari, etc.) to confirm consistent behavior

Test Configuration:

• Various web browsers (Chrome, Firefox, Safari, Edge)
• Different devices (Desktop, Mobile, Tablet)

Checklist

• My code adheres to this project's style guidelines
• I have performed a self-review of my own code
• I have made pertinent documentation changes
• My changes do not introduce new warnings