Likely the biggest change of the tailwind refactors. Only thing of note
is that `tw-flex-1` resolves to `flex: 1 1 0%` while our `gt-f1` was
`flex: 1 1 0`, I don't think it will make any difference. Commands I've
ran:

```sh
perl -p -i -e 's#gt-vm#tw-align-middle#g' web_src/js/**/* templates/**/* models/**/*
perl -p -i -e 's#gt-fw#tw-flex-wrap#g' web_src/js/**/* templates/**/* models/**/*
perl -p -i -e 's#gt-f1#tw-flex-1#g' web_src/js/**/* templates/**/* models/**/*
perl -p -i -e 's#gt-fc#tw-flex-col#g' web_src/js/**/* templates/**/* models/**/*
perl -p -i -e 's#gt-sb#tw-justify-between#g' web_src/js/**/* templates/**/* models/**/*
perl -p -i -e 's#gt-je#tw-justify-end#g' web_src/js/**/* templates/**/* models/**/*
perl -p -i -e 's#gt-jc#tw-justify-center#g' web_src/js/**/* templates/**/* models/**/*
perl -p -i -e 's#gt-ac#tw-content-center#g' web_src/js/**/* templates/**/* models/**/* tests/**/*
perl -p -i -e 's#gt-df#tw-flex#g' web_src/js/**/* templates/**/* models/**/* tests/**/*
perl -p -i -e 's#gt-dib#tw-inline-block#g' web_src/js/**/* templates/**/* models/**/* tests/**/*

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

Follow #29357 
- Replace `gt-w-*` -> `tw-w-*` and remove `gt-w-*`
- Replace `gt-h-*` -> `tw-h-*` and remove `gt-h-*`

* `gt-w-100` => `gt-w-full` to match tailwind
* clarify `gt-hidden` priority

Close #27012

By the way, rename the single-word ID to a long ID.


![image](https://github.com/go-gitea/gitea/assets/2114189/9f05ecc3-0a3d-4612-85e0-da60f7a45d2e)


![image](https://github.com/go-gitea/gitea/assets/2114189/9133808c-bd89-4265-99c5-83b986bd266f)

1. Fine tune the CSS styles, and add more examples
2. Add necessary "dimmer" animation for modal dialogs, otherwise the UI
seems flicking (follow #26469)

Replace #25446, fix #25438

All "cancel" buttons which do not have "type" should not submit the
form, should not be triggered by "Enter".

This is a complete fix for all modal dialogs.

The major change is "modules/aria/modal.js", "devtest" related code is
for demo/test purpose.

Follow #24097 and #24285

And add a devtest page for modal action button testing.
http://localhost:3000/devtest/fomantic-modal

Now the `modal_actions_confirm.tmpl` could support: green / blue /
yellow positive buttons, the negative button is "secondary".

ps: this PR is only a small improvement, there are still a lot of
buttons not having proper colors. In the future these buttons could be
improved by this approach.

These buttons could also be improved according to the conclusion of
#24285 in the future.



![image](https://user-images.githubusercontent.com/2114189/233847773-a6d6b29b-7b5c-490e-8425-40dfd0ad2529.png)


And add GitHub-like single danger button (context:
https://github.com/go-gitea/gitea/issues/24285#issuecomment-1519100312)


![image](https://user-images.githubusercontent.com/2114189/233891566-055d7611-894d-4d5a-baf5-f6369180bf8d.png)

---------

Co-authored-by: silverwind <me@silverwind.io>