fix(nitro): normalise attached and recovered .nitro bundles too

Two more .nitro entry points in the main import path still wrote the
supplied buffer verbatim: an attached `providedNitro` and a bundle pulled
back by `resolveMissingNitro`. Both are real furniture imports, so they
could still land a PNG texture while the SWF, clone and upload paths
produced WebP.

Route both through the same normalisation, falling back to the original
bytes with a warning if the texture cannot be decoded.

src/lib/services/furni-import.ts

@@ -218,6 +218,26 @@ import { classifyFurni } from "@/lib/furni/auto-catalog";
 export { autoPriceFurni } from "@/lib/furni/auto-catalog";
 
 import { autoPriceFurni } from "@/lib/furni/auto-catalog";
+import { toWebpLosslessBundle } from "@/lib/services/swf/nitro-builder";
+
+/**
+ * Store an incoming .nitro as WebP Lossless, whatever format it arrived in, so
+ * every import path ends up with the same on-disk format as the SWF importer.
+ * A texture that cannot be decoded is kept as-is with a warning: the bundle
+ * itself is valid, and dropping a furniture item over a codec edge case is
+ * worse than a slightly larger texture.
+ */
+async function toWebpLosslessOrKeep(
+	bundle: Buffer,
+	warnings: string[],
+): Promise<Buffer> {
+	try {
+		return await toWebpLosslessBundle(bundle);
+	} catch {
+		warnings.push("texture kept in its original format");
+		return bundle;
+	}
+}
 
 /** Get or create a category sub-page under the imported parent page.
  * Caches category page IDs in-memory for CATEGORY_CACHE_TTL_MS to avoid
@@ -654,7 +674,11 @@ export async function importSingleFurni(params: {
 	const mirrorNitroDirs = assetTargets.mirrorDirs.map((d) => d.nitroDir);
 
 	if (params.providedNitro && !existsSync(nitroPath)) {
-		await fs.writeFile(nitroPath, params.providedNitro, { flag: "wx" });
+		await fs.writeFile(
+			nitroPath,
+			await toWebpLosslessOrKeep(params.providedNitro, warnings),
+			{ flag: "wx" },
+		);
 	}
 
 	// ── Download assets in parallel (with retry + validation) ────────
@@ -816,7 +840,12 @@ export async function importSingleFurni(params: {
 	if (!existsSync(nitroPath) && params.resolveMissingNitro) {
 		await onProgress?.("checking_sources");
 		const recovered = await params.resolveMissingNitro(rev);
-		if (recovered) await fs.writeFile(nitroPath, recovered, { flag: "wx" });
+		if (recovered)
+			await fs.writeFile(
+				nitroPath,
+				await toWebpLosslessOrKeep(recovered, warnings),
+				{ flag: "wx" },
+			);
 		else
 			warnings.push(
 				"No matching bundle was recovered from the checked sources. Review source availability or attach the original .nitro file.",