feat(studio): localize catalog studio UI and polish responsive layout

Route all Catalog Studio strings through the admin.studio namespace
(workspace, filters, review, inspector, quality, sync, scale32, organize
imports and page titles/subtitles) with English fallback, and add shared
StudioPage chrome plus a loading skeleton. Tighten mobile padding on the
header and sub-bars.

src/components/admin/studio/use-studio-translations.ts

@@ -1,4 +1,5 @@
 "use client";
+import { useTranslations } from "next-intl";
 import { useState } from "react";
 import { toast } from "sonner";
 import { setFurnidataTranslateEnabled } from "@/actions/import-furni";
@@ -24,6 +25,7 @@ const TRANSLATE_LANGS = [
 ] as const;
 
 export function useStudioTranslations(defaultTranslate: boolean) {
+	const t = useTranslations("admin.studio");
 	// Translation controls (per-import toggle + language selection, plus a global
 	// default that persists to the site setting and seeds the per-import toggle).
 	const ALL_LANGS = TRANSLATE_LANGS as readonly string[];
@@ -52,13 +54,16 @@ export function useStudioTranslations(defaultTranslate: boolean) {
 				const langs = data.languages ?? [];
 				const okCount = langs.filter((l) => l.ok).length;
 				toast.success(
-					`Languages translated (${okCount}/${langs.length} completed)`,
+					t("toasts.languagesTranslated", {
+						ok: okCount,
+						total: langs.length,
+					}),
 				);
 			} else {
-				toast.error(data.error ?? "Translation failed");
+				toast.error(data.error ?? t("toasts.translationFailed"));
 			}
 		} catch {
-			toast.error("Network error while translating languages");
+			toast.error(t("toasts.networkTranslating"));
 		} finally {
 			setBuildingLanguages(false);
 		}
@@ -75,7 +80,7 @@ export function useStudioTranslations(defaultTranslate: boolean) {
 		try {
 			await setFurnidataTranslateEnabled({ enabled: next });
 		} catch {
-			toast.error("Could not save the default translation setting");
+			toast.error(t("toasts.saveDefaultFailed"));
 		}
 	};