Change `--border-radius-circle` to `--border-radius-full` (#30936)

Percentage-based `border-radius` [creates undesirable
ellipse](https://jsfiddle.net/silverwind/j9ko5wnt/4/) on non-square
content. Instead, use pixel value and use same wording `full` like
tailwind does, but increast to 99999px over their 9999px.

tailwind.config.js

@@ -66,7 +66,7 @@ export default {
       'xl': '12px',
       '2xl': '16px',
       '3xl': '24px',
-      'full': 'var(--border-radius-circle)', // 50%
+      'full': 'var(--border-radius-full)',
     },
     fontFamily: {
       sans: 'var(--fonts-regular)',

web_src/css/base.css

@@ -18,7 +18,7 @@
   /* other variables */
   --border-radius: 4px;
   --border-radius-medium: 6px;
-  --border-radius-circle: 50%;
+  --border-radius-full: 99999px; /* TODO: use calc(infinity * 1px) */
   --opacity-disabled: 0.55;
   --height-loading: 16rem;
   --min-height-textarea: 132px; /* padding + 6 lines + border = calc(1.57142em + 6lh + 2px), but lh is not fully supported */
@@ -1166,7 +1166,7 @@ overflow-menu .ui.label {
 
 .color-icon {
   display: inline-block;
-  border-radius: var(--border-radius-circle);
+  border-radius: var(--border-radius-full);
   height: 14px;
   width: 14px;
 }

web_src/css/modules/animations.css

@@ -31,7 +31,7 @@
   border-width: 4px;
   border-style: solid;
   border-color: var(--color-secondary) var(--color-secondary) var(--color-secondary-dark-8) var(--color-secondary-dark-8);
-  border-radius: var(--border-radius-circle);
+  border-radius: var(--border-radius-full);
 }
 
 .is-loading.loading-icon-2px::after {

web_src/css/repo.css

@@ -790,7 +790,7 @@ td .commit-summary {
   width: 34px;
   height: 34px;
   background-color: var(--color-timeline);
-  border-radius: var(--border-radius-circle);
+  border-radius: var(--border-radius-full);
   display: flex;
   float: left;
   margin-left: -33px;