dynamic promo widget

packages/web/src/jsonui/JsonUiHeading.svelte

@@ -0,0 +1,13 @@
+<script lang="ts">
+  export let text: string;
+  export let level: 1|2|3|4|5|6 = 2;
+  const tag = `h${level}` as keyof HTMLElementTagNameMap;
+</script>
+
+<svelte:element this={tag}>{text}</svelte:element>
+
+<style>
+h2 {
+  text-align: center;
+}
+</style>