implement basic placeholder announcement

frontend/components/Domain/Announcement/Announcements/2026-03-27_1_welcome.vue

@@ -0,0 +1,13 @@
+<template>
+  <div>
+    Welcome to Mealie! This is a placeholder test announcement.
+  </div>
+</template>
+
+<script lang="ts">
+import type { AnnouncementMeta } from "~/composables/use-announcements";
+
+export const meta: AnnouncementMeta = {
+  title: "Placeholder Title",
+};
+</script>