docs: fix typos + clarify example in UI docs (#11543)

www/apps/ui/src/examples/command-bar-demo.tsx

@@ -1,11 +1,11 @@
-import { Checkbox, CommandBar, Label } from "@medusajs/ui"
+import { Checkbox, CommandBar, Label, Text } from "@medusajs/ui"
 import * as React from "react"
 
 export default function CommandBarDemo() {
   const [selected, setSelected] = React.useState<boolean>(false)
 
   return (
-    <div className="flex items-center justify-center">
+    <div className="flex justify-center gap-y-2 flex-col">
       <div className="flex items-center gap-x-2">
         <Checkbox
           checked={selected}
@@ -15,6 +15,7 @@ export default function CommandBarDemo() {
         />
         <Label>Item One</Label>
       </div>
+      <div><Text size="small" className="text-ui-fg-muted">Check the box to view the command bar</Text></div>
       <CommandBar open={selected}>
         <CommandBar.Bar>
           <CommandBar.Value>1 selected</CommandBar.Value>