Add theme selection, dark/light mode selection

app/components/ui/dropdown-menu/DropdownMenuShortcut.vue

@@ -0,0 +1,17 @@
+<script setup lang="ts">
+import type { HTMLAttributes } from "vue"
+import { cn } from "@/lib/utils"
+
+const props = defineProps<{
+  class?: HTMLAttributes["class"]
+}>()
+</script>
+
+<template>
+  <span
+    data-slot="dropdown-menu-shortcut"
+    :class="cn('text-muted-foreground ml-auto text-xs tracking-widest', props.class)"
+  >
+    <slot />
+  </span>
+</template>