Remove fomantic text module

[delvh]

Corollary to #26775:
All selectors I found that are actually used and not necessarily present in the current code have been copied to web_src/css/base.css.
Everything else should be a clean removal.

[silverwind]

We can potentially drop the !important from the .text.red classes etc, but it might have a side-effect or two.

[delvh]

Let's leave that for follow-up PRs…

[silverwind]

It'll likely be no issue, 2 classes is heavier than many things. But yes, we can do this another time, let's not forget it.

Edit: On second thought, let's keep important for now. I forsee some issues with the deeply nested repo selectors for example.

[delvh]

@wxiaoguang please re-review.