add mhvtl detect vendor

frontend/src/api/tape.ts

@@ -26,6 +26,7 @@ export interface VirtualTapeLibrary {
   name: string
   mhvtl_library_id: number
   storage_path: string
+  vendor?: string
   slot_count: number
   drive_count: number
   is_active: boolean

frontend/src/pages/TapeLibraries.tsx

@@ -365,7 +365,11 @@ export default function TapeLibraries() {
                             </td>
                             <td className="py-4 px-6">
                               <p className="text-white text-sm font-medium">
-                                {isVTL ? 'MHVTL' : 'physical' in library ? (library as PhysicalTapeLibrary).vendor : 'N/A'}
+                                {isVTL 
+                                  ? (library as VirtualTapeLibrary).vendor || 'MHVTL'
+                                  : 'physical' in library 
+                                    ? (library as PhysicalTapeLibrary).vendor 
+                                    : 'N/A'}
                               </p>
                               <p className="text-text-secondary text-xs">
                                 LTO-8 • {library.drive_count} {library.drive_count === 1 ? 'Drive' : 'Drives'}