feat: auto-translate furnidata per import (nl/en/de/fr/es/tr/it)

Generate localized FurnitureData_<lang>.json files from the master
FurnitureData.json + official Habbo hotel translations. Fetches per-hotel
furnidata with in-memory cache (6h TTL), maps by classname (* variant
aware), and overrides name/description where a translation exists.

Full rebuild after every batch/batch-regen/clone import and as admin
GET ?action=build-languages; single imports patch incrementally via
patchLocalizedFurniDataEntries. Failures are best-effort and never fail
the import itself. Files are written to every configured gamedata write
path (primary + mirrors) so /gamedata/config/FurnitureData_<lang>.json
is available for per-language Nitro clients.

New service: src/lib/services/furni-data-i18n.ts with
buildLocalizedFurniDataFiles, patchLocalizedFurniDataEntries,
FURNIDATA_LANGUAGES (nl/en/de/fr/es/tr/it) and applyTranslationsForTest.

src/app/api/admin/import/furni/batch-regen/route.ts

@@ -14,6 +14,7 @@ import {
 	reconcileFurniDataWithItemsBase,
 	verifyAndFixSpriteIds,
 } from "@/lib/services/furni-data";
+import { buildLocalizedFurniDataFiles } from "@/lib/services/furni-data-i18n";
 import {
 	downloadFile,
 	ensureDirectories,
@@ -277,6 +278,18 @@ export const POST = withAdmin(
 				// Repair any sprite_id drift so the client renders the right item
 				const spriteVerify = await verifyAndFixSpriteIds();
 
+				let languages: Awaited<
+					ReturnType<typeof buildLocalizedFurniDataFiles>
+				> = [];
+				try {
+					languages = await buildLocalizedFurniDataFiles();
+				} catch (err) {
+					console.warn(
+						"[batch-regen] Localized furnidata build failed:",
+						(err as Error).message,
+					);
+				}
+
 				send({
 					type: "regen_complete",
 					succeeded,
@@ -293,6 +306,7 @@ export const POST = withAdmin(
 					offerRebuildFixed: offerRebuild.fixed,
 					spriteChecked: spriteVerify.checked,
 					spriteFixed: spriteVerify.fixed,
+					languages,
 					duration: Date.now() - startTime,
 				});