APP-223 Bump tailwind major version

[PatFawbertMills]

What's changed

• Tailwind major breaking change upgrade from v3 -> v4
• Lots of small UI fixes along the way
• Removal of all old theme configuration
• Migration over to .css files
• Removal of all scss
• Housekeeping of some smaller components as drive-bys

Proposed version

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[linear]

APP-223 Upgrade tailwind to the latest v4 version

[github-actions]

size-limit report 📦

Path	Size
Next static files	307.68 KB (-0.23% 🔽)

[jesskelsall]

On the whole looks solid. I've spot checked some of the places where Tailwind is used and am happy. I have a few queries about some of the specifics of the stylesheets which I'd like addressing before I approve.

[jesskelsall]

Approved after my comments were addressed and with pragmatic considerations for getting this working for now. We'll continue to improve our Tailwind usage as new components are built.