feat(Toast): implement progress duration

Resolves #51

playground/app.config.ts

@@ -2,7 +2,7 @@ export default defineAppConfig({
   toaster: {
     position: 'bottom-right' as const,
     expand: true,
-    duration: 60000
+    duration: 5000
   },
   ui: {
     primary: 'sky',

playground/pages/toast.vue

@@ -109,7 +109,7 @@ function removeToast () {
 
 <template>
   <div class="flex flex-col items-center gap-8">
-    <div>
+    <div class="flex flex-col gap-2">
       <URadioGroup v-model="appConfig.toaster.position" :options="positions" />
       <UCheckbox v-model="appConfig.toaster.expand" label="Expand" class="mt-1" />
       <UInput v-model="appConfig.toaster.duration" label="Duration" type="number" class="mt-1" />