feat: implement localization for models section

- Added a new copy module to handle translations for models-related components.
- Integrated translation functionality into ProviderPickerDialog, ProvidersSection, RequestContentDialog, UsageBarChart, and UsageHistorySection.
- Updated messages for various UI elements to support multiple languages.
- Refactored usage history functions to accept locale for date formatting.
- Enhanced user experience by providing localized strings for success/error messages and UI labels.

src/pages/Models/components/RequestContentDialog.tsx

@@ -1,3 +1,5 @@
+import { useLocale } from '../../../i18n';
+import { useModelsCopy } from '../copy';
 import DialogSurface from './DialogSurface';
 import type { UsageHistoryEntry } from '../usage-history';
 
@@ -7,13 +9,13 @@ type RequestContentDialogProps = {
   onClose: () => void;
 };
 
-function formatUsageTimestamp(timestamp?: string): string {
+function formatUsageTimestamp(timestamp: string | undefined, locale: string): string {
   if (!timestamp) return '';
 
   const date = new Date(timestamp);
   if (Number.isNaN(date.getTime())) return timestamp;
 
-  return new Intl.DateTimeFormat(undefined, {
+  return new Intl.DateTimeFormat(locale, {
     month: 'short',
     day: 'numeric',
     hour: '2-digit',
@@ -26,12 +28,16 @@ export default function RequestContentDialog({
   entry,
   onClose,
 }: RequestContentDialogProps) {
+  const locale = useLocale();
+  const t = useModelsCopy();
+
   return (
     <DialogSurface
       open={open}
       onClose={onClose}
-      title="Request Content"
-      subtitle={entry ? `${entry.model || 'Unknown Model'} • ${formatUsageTimestamp(entry.timestamp)}` : undefined}
+      title={t('models.usage.requestContent.title')}
+      subtitle={entry ? `${entry.model || t('models.common.unknownModel')} • ${formatUsageTimestamp(entry.timestamp, locale)}` : undefined}
+      closeLabel={t('models.common.closeDialog')}
       widthClassName="max-w-[800px]"
     >
       <div className="max-h-[60vh] overflow-y-auto rounded-[16px] border border-black/6 bg-white p-5 shadow-sm dark:border-white/8 dark:bg-[#1f1f22]">