fix(ui): remove !important amber-50 dark override from globals.css

This override was blocking all dark: Tailwind classes on amber-50 elements.
Components now use explicit dark:bg-amber-950/30 instead.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/web/src/app/globals.css

@@ -343,9 +343,6 @@
 .dark .text-purple-700 {
   color: rgb(196 181 253) !important;
 }
-.dark .bg-amber-50 {
-  background-color: rgb(120 53 15) !important;
-}
 
 /* Modal / overlay */
 .dark .shadow-2xl {