message: Fix width of tracker items
diff: "heading icon"
  "milestone icon";
  background: transparent;
  + width: calc(100% - var(--boxel-sp-sm) * 2);
  color: var(--boxel-light-200);
  margin: 0 var(--boxel-sp);
  border-radius: var(--boxel-border-radius-sm);
  