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/components/hooks/useMessages.ts

@@ -1,47 +1,11 @@
 import { useTranslations } from 'next-intl';
-import { createElement, type ReactNode } from 'react';
-import { labels, type MessageDescriptor, messages } from '@/components/messages';
+import { labels, messages } from '@/components/messages';
 import type { ApiError } from '@/lib/types';
 
-type FormatMessage = (
-  descriptor: MessageDescriptor,
-  values?: Record<string, string | number | boolean | null | undefined>,
-  opts?: any,
-) => string | null;
-
-interface FormattedMessageProps extends MessageDescriptor {
-  values?: Record<string, ReactNode>;
-}
-
-interface UseMessages {
-  formatMessage: FormatMessage;
-  messages: typeof messages;
-  labels: typeof labels;
-  getMessage: (id: string) => string;
-  getErrorMessage: (error: ApiError) => string | undefined;
-  FormattedMessage: (props: FormattedMessageProps) => ReactNode;
-}
-
-export function useMessages(): UseMessages {
+export function useMessages() {
   const t = useTranslations();
 
-  const formatMessage = (
-    descriptor: MessageDescriptor,
-    values?: Record<string, string | number | boolean | null | undefined>,
-  ) => {
-    if (!descriptor) return null;
-    try {
-      return t(descriptor.id, values);
-    } catch {
-      return descriptor.defaultMessage || descriptor.id;
-    }
-  };
-
-  const getMessage = (id: string) => {
-    const message = Object.values(messages).find(value => value.id === `message.${id}`);
-
-    return message ? formatMessage(message) : id;
-  };
+  const getMessage = (id: string) => t(`message.${id}`);
 
   const getErrorMessage = (error: ApiError) => {
     if (!error) {
@@ -53,50 +17,5 @@ export function useMessages(): UseMessages {
     return code ? getMessage(code) : error?.message || 'Unknown error';
   };
 
-  function FormattedMessage({ id, defaultMessage, values }: FormattedMessageProps) {
-    if (
-      !values ||
-      Object.values(values).every(v => typeof v === 'string' || typeof v === 'number')
-    ) {
-      try {
-        return t(id, values as any);
-      } catch {
-        return defaultMessage || id;
-      }
-    }
-
-    // For JSX values: get the raw ICU template and manually interpolate
-    let template: string;
-    try {
-      template = t.raw(id) as string;
-    } catch {
-      template = defaultMessage || id;
-    }
-
-    if (typeof template !== 'string') {
-      return defaultMessage || id;
-    }
-
-    // Split on {placeholder} tokens and interleave with values
-    const parts: ReactNode[] = [];
-    const regex = /\{(\w+)\}/g;
-    let lastIndex = 0;
-
-    for (let match = regex.exec(template); match !== null; match = regex.exec(template)) {
-      if (match.index > lastIndex) {
-        parts.push(template.slice(lastIndex, match.index));
-      }
-      const key = match[1];
-      parts.push(values[key] !== undefined ? values[key] : match[0]);
-      lastIndex = regex.lastIndex;
-    }
-
-    if (lastIndex < template.length) {
-      parts.push(template.slice(lastIndex));
-    }
-
-    return createElement('span', null, ...parts);
-  }
-
-  return { formatMessage, messages, labels, getMessage, getErrorMessage, FormattedMessage };
+  return { t, messages, labels, getMessage, getErrorMessage };
 }