feat(combobox): add disabled prop and improve styling

- Add disabled prop to combobox component to support disabled state
- Update styling to include better focus states and border color

app/components/pub/custom-ui/form/combobox.vue

@@ -15,6 +15,7 @@ const props = defineProps<{
   searchPlaceholder?: string
   emptyMessage?: string
   class?: string
+  disabled?: boolean
 }>()
 
 const emit = defineEmits<{
@@ -63,13 +64,14 @@ function onSelect(item: Item) {
     <PopoverTrigger as-child>
       <Button
       :id="props.id"
+      :disabled="props.disabled"
       variant="outline"
       role="combobox"
       :aria-expanded="open"
       :aria-controls="`${props.id}-list`"
       :aria-describedby="`${props.id}-search`"
       :class="cn(
-        'w-full justify-between border-black bg-white hover:bg-gray-50 text-sm font-normal',
+        'w-full justify-between border-1 border-gray-400 bg-white hover:bg-gray-50 text-sm font-normal focus:outline-none focus:ring-1 focus:ring-black',
         !modelValue && 'text-muted-foreground',
         props.class,
       )"