fix(metadata): get series from api

static/index.html

@@ -246,6 +246,9 @@
         <p class="muted mono" id="detail-path"></p>
         <div class="row">
           <button value="cancel" class="secondary">Abbrechen</button>
+          <button type="button" id="detail-retag" class="secondary" hidden>
+            Speichern &amp; neu taggen
+          </button>
           <button value="ok" id="detail-save">Speichern</button>
         </div>
       </form>