Fix bulk import: group tagless files by folder, use folder name as search fallback

src/app/api/admin/bulk-import/scan/route.ts

@@ -159,7 +159,29 @@ export async function POST(request: NextRequest) {
               let hasActiveRequest = false;
 
               try {
-                const searchResult = await audibleService.search(book.searchTerm);
+                // If the scanner extracted an ASIN directly from the folder name,
+                // try an exact ASIN lookup first — faster and more accurate than
+                // a text search. Fall back to text search if it fails or returns
+                // no result.
+                let searchResult: Awaited<ReturnType<typeof audibleService.search>> | null = null;
+
+                if (book.extractedAsin) {
+                  try {
+                    const asinResult = await audibleService.search(book.extractedAsin);
+                    if (
+                      asinResult.results.length > 0 &&
+                      asinResult.results[0].asin === book.extractedAsin
+                    ) {
+                      searchResult = asinResult;
+                    }
+                  } catch {
+                    /* ASIN lookup failed — fall through to text search */
+                  }
+                }
+
+                if (!searchResult) {
+                  searchResult = await audibleService.search(book.searchTerm);
+                }
 
                 if (searchResult.results.length > 0) {
                   match = searchResult.results[0];
@@ -208,6 +230,7 @@ export async function POST(request: NextRequest) {
                 audioFileCount: book.audioFileCount,
                 totalSizeBytes: book.totalSizeBytes,
                 metadataSource: book.metadataSource,
+                extractedAsin: book.extractedAsin,
                 searchTerm: book.searchTerm,
                 audioFiles: book.audioFiles,
                 match: match