chore: uniformize icons in Button / Input / Select / SelectMenu

Also adds `loading` to `Select` and `SelectMenu`

src/runtime/app.config.ts

@@ -399,6 +399,7 @@ const select = {
     size: 'sm',
     color: 'white',
     variant: 'outline',
+    loadingIcon: 'i-heroicons-arrow-path-20-solid',
     trailingIcon: 'i-heroicons-chevron-down-20-solid'
   }
 }