!feat(categories): add 3 categories for artists

- albums: album found
- artists: found the artist, not the album
- notfound: not found on bandcamp (or limited by api)

API on refresh changes.
Use a extern script instead of write it in html page.

static/css/style.css

@@ -1,5 +1,5 @@
 h1 {
-    color: red;
+    color: green;
 }
 
 td, th {
@@ -14,3 +14,7 @@ footer {
     display: grid;
     grid-template-columns: 1fr 1fr 1fr;
 }
+
+.only-artist {
+    color: red;
+}