General: Trim the bare button class to what Tailwind does not already reset

Six of its nine declarations repeated Tailwind's preflight, which already gives
buttons margin, padding and border from the universal reset and font, colour and
background from the form element rule. Repeating them bought nothing and only
widened the set of properties the class could take away from the utilities on the
same element, which is how the sidebar lost its highlight and its padding.

What is left is what preflight does not cover: buttons come out centred, and
since v4 they carry a default cursor rather than a pointer. Ten of the eleven call
sites already pass cursor-pointer themselves, so that one is close to redundant
too, but rating.component relies on it.

appearance: none went with the rest. It was overriding preflight's
appearance: button, and with background and border already flat there is no native
chrome left for it to suppress.

Confirmed against the compiled stylesheet: the rule is now two declarations, the
preflight rules that cover the removed ones are still present, and btn-bare stays
in the components layer with the utilities after it.

Verified: 2031 client tests, typecheck, eslint with no errors, a11y lint, the
production build and prettier.

Co-Authored-By: Claude <noreply@anthropic.com>

Author: az108

src/main/webapp/content/scss/global.scss

@@ -9,23 +9,17 @@
 @plugin "tailwindcss-primeui";
 @custom-variant dark (&:where(.tum-apply-dark-mode, .tum-apply-dark-mode *)); //dark mode configuration
 
-/* Visual reset for native <button> elements used purely as clickable containers
-   (cards, list rows, icon triggers). Strips default chrome so they inherit
-   surrounding typography and layout, while keeping their accessibility benefits.
-
-   Declared in the components layer on purpose. Unlayered rules outrank every layered
-   one no matter their specificity, so leaving this outside a layer would let the reset
-   beat the Tailwind utilities on the same element and silently drop their background,
-   padding and colour. The components layer sits before utilities, so utilities win. */
+/* For native <button> elements used purely as clickable containers (cards, list rows,
+   icon triggers). Only covers what Tailwind's preflight leaves behind: buttons come out
+   centred and, since v4, with a default cursor. Background, border, padding, margin, font
+   and colour are already reset there, so repeating them here only creates something that
+   can fight the utilities on the same element.
+
+   Kept in the components layer for that same reason. Unlayered rules outrank every layered
+   one whatever their specificity, so declaring this outside a layer would let it beat the
+   utilities instead. Components sits before utilities, so utilities win. */
 @layer components {
   .btn-bare {
-    appearance: none;
-    background: transparent;
-    border: 0;
-    padding: 0;
-    margin: 0;
-    font: inherit;
-    color: inherit;
     text-align: inherit;
     cursor: pointer;
   }