Add TS type information

src/lib/components/Card.svelte

@@ -1,7 +1,45 @@
 <script lang="ts">
-  let { children, fullwidth = false, ...restProps } = $props();
+  import type { Snippet } from "svelte";
+
+  interface CardProps {
+    children: Snippet;
+
+    /** The URL for a possible header image. Leave undefined for no header image. Set to empty string for an image not yet loaded. */
+    imgsrc?: string | undefined;
+
+    /** The id of the header image element for JS access. */
+    imgid?: string | undefined;
+
+    /** Hide the header image element. It can be shown by removing the "hidden" property using JS and the imgid. */
+    imghidden?: boolean;
+
+    /** Enable to give the card the "w-full" class. */
+    fullwidth?: boolean;
+  }
+
+  let {
+    children,
+    imgsrc = undefined,
+    imgid = undefined,
+    imghidden = false,
+    fullwidth = false,
+    ...restProps
+  }: CardProps = $props();
 </script>
 
-<div class="card bg-white p-2 shadow {fullwidth ? 'w-full' : 'w-auto'}" {...restProps}>
-  {@render children()}
+<div class="card overflow-hidden bg-white shadow {fullwidth ? 'w-full' : 'w-auto'}">
+  <!-- Allow empty strings for images that only appear after user action -->
+  {#if imgsrc !== undefined}
+    <img
+      id={imgid}
+      src={imgsrc}
+      alt="Card header"
+      draggable="false"
+      class="select-none shadow"
+      hidden={imghidden}
+    />
+  {/if}
+  <div class="p-2" {...restProps}>
+    {@render children()}
+  </div>
 </div>