docs(app): framework select global (#2719)

Co-authored-by: harlan <harlan@harlanzw.com>

docs/app/components/FrameworkSelect.vue

@@ -0,0 +1,25 @@
+<script setup lang="ts">
+const { framework, frameworks } = useSharedData()
+</script>
+
+<template>
+  <UDropdownMenu
+    v-slot="{ open }"
+    :modal="false"
+    :items="frameworks"
+    :ui="{ content: 'w-(--radix-dropdown-menu-trigger-width)' }"
+  >
+    <UButton
+      color="neutral"
+      variant="outline"
+      v-bind="frameworks.find(f => f.value === framework)"
+      block
+      trailing-icon="i-lucide-chevron-down"
+      :class="[open && 'bg-[var(--ui-bg-elevated)]']"
+      :ui="{
+        trailingIcon: ['transition-transform duration-200', open ? 'rotate-180' : undefined].filter(Boolean).join(' ')
+      }"
+      class="-mx-2 w-[calc(100%+1rem)]"
+    />
+  </UDropdownMenu>
+</template>