combobox: improve props, fix placement with scroll

src/routes/+page.svelte

@@ -49,7 +49,7 @@
 		name="example-combobox"
 		label="Select an option"
 		placeholder="Choose..."
-		items={[
+		options={[
 			{ value: 'option1', label: 'Option 1' },
 			{ value: 'option2', label: 'Option 2' },
 			{ value: 'option3', label: 'Option 3' }