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/route.ts

@@ -14,6 +14,10 @@ import {
 	reconcileFurniDataWithItemsBase,
 	verifyAndFixSpriteIds,
 } from "@/lib/services/furni-data";
+import {
+	buildLocalizedFurniDataFiles,
+	patchLocalizedFurniDataEntries,
+} from "@/lib/services/furni-data-i18n";
 import {
 	autoPriceFurni,
 	CATEGORY_PAGE,
@@ -189,6 +193,11 @@ export const GET = withAdmin(
 			});
 		}
 
+		if (action === "build-languages") {
+			const languages = await buildLocalizedFurniDataFiles();
+			return apiOk({ languages });
+		}
+
 		// Missing nitro endpoint: returns only imported items missing .nitro files
 		if (action === "missing-nitro") {
 			const pageNum = parseInt(
@@ -471,6 +480,18 @@ export const POST = withAdmin(
 			// Verify + fix interaction_modes_count once for the whole batch
 			const verification = await verifyAndFixInteractionModesCount();
 
+			// Rebuild all localized furnidata files (best effort)
+			let languages: Awaited<ReturnType<typeof buildLocalizedFurniDataFiles>> =
+				[];
+			try {
+				languages = await buildLocalizedFurniDataFiles();
+			} catch (err) {
+				console.warn(
+					"[import-furni] Localized furnidata build failed:",
+					(err as Error).message,
+				);
+			}
+
 			const succeeded = results.filter((r) => r.ok).length;
 			const failed = results.filter((r) => !r.ok).length;
 
@@ -492,6 +513,7 @@ export const POST = withAdmin(
 				spriteChecked: spriteVerify.checked,
 				spriteFixed: spriteVerify.fixed,
 				interactionFixed: verification.fixed,
+				languages,
 			});
 		}
 
@@ -562,6 +584,21 @@ export const POST = withAdmin(
 		// Verify + fix interaction_modes_count (single consolidated pass)
 		const verification = await verifyAndFixInteractionModesCount();
 
+		// Patch localized furnidata files for this single furni (best effort)
+		let languagesPatch: Awaited<
+			ReturnType<typeof patchLocalizedFurniDataEntries>
+		> = [];
+		try {
+			languagesPatch = await patchLocalizedFurniDataEntries([
+				{ classname, name, description: description ?? "" },
+			]);
+		} catch (err) {
+			console.warn(
+				"[import-furni] Localized patch failed:",
+				(err as Error).message,
+			);
+		}
+
 		logAudit({
 			userId: ctx.session.user.id,
 			action: "furni_import",
@@ -595,6 +632,7 @@ export const POST = withAdmin(
 			spriteChecked: spriteVerify.checked,
 			spriteFixed: spriteVerify.fixed,
 			interactionFixed: verification.fixed,
+			languages: languagesPatch,
 			spriteCount: result.spriteCount,
 			warnings: result.warnings,
 		});