Update UI and improve i18n loading logic

Major changes include enhancements to the UI and modifications to the i18n loading logic to more effectively handle namespaces. Several components were updated to improve readability and layout consistency. The i18n loading logic now includes additional handling for waiting until all namespaces are loaded before the i18n instance is returned, with a warning if it takes longer than expected. Furthermore, code have been refactored for fonts, buttons, and other UI elements.

packages/billing/gateway/src/components/pricing-table.tsx

@@ -377,7 +377,7 @@ function PlanIntervalSwitcher(
           {
             'rounded-r-none border-r-transparent': index === 0,
             'rounded-l-none': index === props.intervals.length - 1,
-            ['hover:text-primary border']: !selected,
+            ['hover:text-primary border text-muted-foreground']: !selected,
             ['font-semibold cursor-default hover:text-initial hover:bg-background']:
               selected,
           },
@@ -444,7 +444,7 @@ function DefaultCheckoutButton(
     <Link className={'w-full'} href={linkHref}>
       <Button
         size={'lg'}
-        className={'ring-primary w-full ring-2'}
+        className={'border-primary w-full border rounded-lg'}
         variant={props.highlighted ? 'default' : 'outline'}
       >
         <span>