feat(i18n): translate hardcoded strings across print, public recipe, and recipe management UI

Wires dozens of components and server pages to next-intl instead of hardcoded
English text, and adds a lightweight getMessages/formatMessage helper for
server components (print pages, public recipe page, cook metadata) since
next-intl/server isn't wired into this app's routing. Backfills missing
en/fr message keys that existing code already referenced but fr.json lacked.

apps/web/components/recipe/recipes-header.tsx

@@ -22,13 +22,14 @@ import { UrlImportDialog } from "./url-import-dialog";
 
 function TagFilterInput({ value, onChange }: { value: string; onChange: (v: string) => void }) {
   const [local, setLocal] = useState(value);
+  const t = useTranslations("recipes");
   return (
     <input
       value={local}
       onChange={(e) => setLocal(e.target.value)}
       onKeyDown={(e) => { if (e.key === "Enter") onChange(local); }}
       onBlur={() => onChange(local)}
-      placeholder="Filter by tag…"
+      placeholder={t("filterByTag")}
       className="w-full h-7 px-2 text-sm rounded-md border border-input bg-background focus:outline-none focus:ring-1 focus:ring-ring"
     />
   );