message: small refactor for consistency.
diff: import { onMount } from "svelte";
  import { slide } from "svelte/transition";
  - export let clazz = "";
  + let clazz = "";
  + export { clazz as class };
  export let storageKey: string;
  export let location: "top" | "bottom" = "top";
  showBanner = false;
  window.localStorage.setItem(storageKey, "true");
  if (clazz === "announcement-banner") {
  - document.body.classList.remove("banner-is-shown")
  + document.body.classList.remove("banner-is-shown");
  }
  };
  onMount(() => {
  showBanner = !window.localStorage.getItem(storageKey);
  if (showBanner && clazz === "announcement-banner") {
  - document.body.classList.add("banner-is-shown")
  + document.body.classList.add("banner-is-shown");
  }
  });
  </script>
  