i18n: translate meal/drink pairing, nutrition, comments, DMs, people search, URL import

Full sweep of hardcoded English strings across:
- Meal pairing and drink pairing dialogs (titles, descriptions, role/
  type labels, regenerate/generate buttons, progress labels) — also
  fixed drink type labels that had French text hardcoded regardless
  of locale ("Sans alcool"/"Chaud").
- Nutrition panel — had no useTranslations at all.
- Comments: header, empty/loading state, post/reply/cancel/delete
  buttons, relative timestamps (just now/Xm ago/Xh ago/Xd ago), and
  comment-reactions' toasts + aria-labels.
- Rating stars toasts.
- Direct messages: thread, conversation list, message button, both
  /messages pages.
- People search page and component.
- URL import dialog (title, description, buttons, toasts).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

apps/web/components/social/message-button.tsx

@@ -3,11 +3,13 @@
 import { useState } from "react";
 import { useRouter } from "next/navigation";
 import { toast } from "sonner";
+import { useTranslations } from "next-intl";
 import { MessageCircle } from "lucide-react";
 import { Button } from "@/components/ui/button";
 
 export function MessageButton({ targetUsername }: { targetUsername: string }) {
   const router = useRouter();
+  const t = useTranslations("messages");
   const [loading, setLoading] = useState(false);
 
   async function startConversation() {
@@ -20,7 +22,7 @@ export function MessageButton({ targetUsername }: { targetUsername: string }) {
       });
       if (!res.ok) {
         const err = await res.json() as { error?: string };
-        toast.error(err.error ?? "Failed to start conversation");
+        toast.error(err.error ?? t("startConversationFailed"));
         return;
       }
       const { conversationId } = await res.json() as { conversationId: string };
@@ -33,7 +35,7 @@ export function MessageButton({ targetUsername }: { targetUsername: string }) {
   return (
     <Button variant="outline" size="sm" onClick={() => { void startConversation(); }} disabled={loading}>
       <MessageCircle className="h-3.5 w-3.5" />
-      Message
+      {t("messageButton")}
     </Button>
   );
 }