Simplify i18n: remove old react-intl artifacts, rename formatMessage to t, replace FormattedMessage with t.rich().

- Rewrite messages.ts to plain string key maps (remove MessageDescriptor)
- Rewrite useMessages hook to expose t from useTranslations() directly
- Rename formatMessage → t across 193 consumer files
- Replace custom FormattedMessage component with next-intl t.rich()
- Update 52 language files to use rich text tags (<b>, <a>)
- Remove all direct imports from @/components/messages in favor of useMessages()

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

src/app/(main)/websites/WebsiteAddForm.tsx

@@ -11,7 +11,7 @@ export function WebsiteAddForm({
   onSave?: () => void;
   onClose?: () => void;
 }) {
-  const { formatMessage, labels, messages } = useMessages();
+  const { t, labels, messages } = useMessages();
   const { mutateAsync, error, isPending } = useUpdateQuery('/websites', { teamId });
 
   const handleSubmit = async (data: any) => {
@@ -26,21 +26,21 @@ export function WebsiteAddForm({
   return (
     <Form onSubmit={handleSubmit} error={error?.message}>
       <FormField
-        label={formatMessage(labels.name)}
+        label={t(labels.name)}
         data-test="input-name"
         name="name"
-        rules={{ required: formatMessage(labels.required) }}
+        rules={{ required: t(labels.required) }}
       >
         <TextField autoComplete="off" />
       </FormField>
 
       <FormField
-        label={formatMessage(labels.domain)}
+        label={t(labels.domain)}
         data-test="input-domain"
         name="domain"
         rules={{
-          required: formatMessage(labels.required),
-          pattern: { value: DOMAIN_REGEX, message: formatMessage(messages.invalidDomain) },
+          required: t(labels.required),
+          pattern: { value: DOMAIN_REGEX, message: t(messages.invalidDomain) },
         }}
       >
         <TextField autoComplete="off" />
@@ -48,11 +48,11 @@ export function WebsiteAddForm({
       <Row justifyContent="flex-end" paddingTop="3" gap="3">
         {onClose && (
           <Button isDisabled={isPending} onPress={onClose}>
-            {formatMessage(labels.cancel)}
+            {t(labels.cancel)}
           </Button>
         )}
         <FormSubmitButton data-test="button-submit" isDisabled={false}>
-          {formatMessage(labels.save)}
+          {t(labels.save)}
         </FormSubmitButton>
       </Row>
     </Form>