feat(ui): update upload status with error message if import failed

Part-of: <https://dev.funkwhale.audio/funkwhale/funkwhale/-/merge_requests/2308>

changes/changelog.d/1999.enhancement

@@ -0,0 +1 @@
+Update upload status when import fails (#1999)

front/src/components/library/FileUpload.vue

@@ -128,6 +128,15 @@ useWebSocketHandler('import.status_updated', async (event) => {
   // TODO (wvffle): Why?
   await nextTick()
 
+  if (event.new_status === 'errored') {
+    for (const file of files.value) {
+      if (file.response?.uuid === event.upload.uuid) {
+        file.error = event.new_status
+        break
+      }
+    }
+  }
+
   uploads[event.old_status] -= 1
   uploads[event.new_status] += 1
   uploads.objects[event.upload.uuid] = event.upload