Upgrade project to TailwindCSS v4 & Skeleton v4

I need help updating codebase to TailwindCSS v4 and Skeleton.dev v4 for our project from current base.

Use these guides to Migration tw3 to tw4 and Skeleton v2 to v3
https://next.skeleton.dev/docs/get-started/migrate-from-v2

Migration skeleton.dev v3 to v4
https://next.skeleton.dev/docs/get-started/migrate-from-v3

The project would and need to be adapted using the existing migration scripts from tailwindcss & skeleton.dev

Grab updated theme from https://github.com/SveltyCMS/SveltyCMS/blob/nx2/apps/shared-theme/sveltycms.css

We started very early with tw4 & skeleton.dev v3 see but toast and modals where incomplete so this is just for references if stuck see: https://github.com/SveltyCMS/SveltyCMS/tree/skeletonV3%26TW4

Commit full updated theme changes via pull request to "next" branch and leave a git star.

If u find issues in this process please fix in
this while migration (like Avatar delete modals)

This task should not take more than 3 days. Place your final quote with time frame.