Reduce application.css file size

[coalest]

Description

I noticed our main CSS file is quite large (> 3 mb). Reducing it should improve browser performance.

This PR presents two changes:

1. Fix AdminLTE CSS duplication. We were accidentally bundling all the AdminLTE CSS twice, since we had @import 'AdminLTE' repeated in two files. From the documentation:

⚠️ Heads up!

If the same stylesheet is imported more than once, it will be evaluated again each time. If it just defines functions and mixins, this usually isn’t a big deal, but if it contains style rules they’ll be compiled to CSS more than once.

2. Replace the regular AdminLTE CSS file (version 3.2.0) to the version bundled without the dark-mode related CSS since we aren't using dark mode as far as I can tell. (We can always add it back if we want to implement dark mode in the future.)

Type of change

• Internal

How Has This Been Tested?

I did some side-by-side comparison with staging after the changes and everything looks the same to me. 🤷

Screenshots

Reduces the file size by about 2 megabytes in raw file size (160 kb over the wire).
Before:

After:

[coalest]

Since we are removing the second AdminLTE import (from custom.scss), we have to move this import after the bootstrap import. Because AdminLTE depends on and includes bootstrap 4.6 inside it's css, and we want bootstrap 4.6 to have priority over the other bootstrap (version 5.2).

[coalest]

This @extend call required the adminLTE import, but looks like we aren't using this wrapper-form-feedback class anywhere so I went ahead and removed it.

[dorner]

OK on my end.

[cielf]

I didn't check absolutely everything, but enough breadth and depth that I'm confident in this.

[github-actions]

@coalest: Your PR Reduce application.css file size is part of today's Human Essentials production release: 2025.01.26.
Thank you very much for your contribution!