Remove fomantic text module (#26777)

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.

web_src/css/base.css

@@ -1175,6 +1175,10 @@ img.ui.avatar,
   color: var(--color-gold) !important;
 }
 
+.text.small {
+  font-size: 0.75em;
+}
+
 /* FIXME: this is a serious pollution, do not use this for "float: left" anymore */
 .ui.left:not(.action) {
   float: left;
@@ -1257,10 +1261,6 @@ img.ui.avatar,
   text-align: right !important;
 }
 
-.ui .text.small {
-  font-size: 0.75em;
-}
-
 .ui .text.normal {
   font-weight: var(--font-weight-normal);
 }