chore: various UI problems (#38263)

1. fix dirty "list" styles for "githooks" and "webhooks"
2. fix git hook edit page layout
3. fix codemirror editor styles
4. fix incorrect "ui attached header" width

web_src/css/modules/menu.css

@@ -27,6 +27,7 @@
 .ui.menu:not(.vertical) .item {
   display: flex;
   align-items: center;
+  gap: var(--gap-inline);
 }
 
 .ui.menu .item {