send processing album colors to a background thread

- use white color as default album page play button color
- return 404 if album is None on get_album_bio()

src/components/contextMenu.vue

@@ -57,7 +57,7 @@ const context = useContextStore();
   top: 0;
   left: 0;
   width: 12rem;
-  z-index: 10;
+  z-index: 10000;
   transform: scale(0);
 
   padding: $small;
@@ -68,12 +68,10 @@ const context = useContextStore();
   .context-item {
     width: 100%;
     display: flex;
-    justify-content: flex-start;
     align-items: center;
     cursor: default;
     padding: $small;
     border-radius: $small;
-    color: rgb(255, 255, 255);
     position: relative;
     text-transform: capitalize;