fix: rename Office Translator to Wordly everywhere

Replaced all references to "Office Translator" with "Wordly" across
i18n translations (13 locales), auth forms, layout components, admin
sidebar, and page metadata.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

frontend/src/app/admin/AdminSidebar.tsx

@@ -23,7 +23,7 @@ export function AdminSidebar() {
           <Languages className="size-3 text-background" />
         </div>
         <span className="text-xs font-semibold tracking-tight text-foreground">
-          Office Translator
+          Wordly
         </span>
         <Badge
           variant="outline"