chore: add test for accessors

packages/svelte/tests/runtime-runes/samples/accessors-props/_config.js

@@ -0,0 +1,15 @@
+import { ok, test } from '../../test';
+import { flushSync } from 'svelte';
+
+export default test({
+	html: `<p>0</p>`,
+
+	async test({ assert, target, instance }) {
+		const p = target.querySelector('p');
+		ok(p);
+		flushSync(() => {
+			instance.count++;
+		});
+		assert.equal(p.innerHTML, '1');
+	}
+});

packages/svelte/tests/runtime-runes/samples/accessors-props/main.svelte

@@ -0,0 +1,9 @@
+<script>
+	let { count=0 } = $props();
+
+	export {
+		count
+	}
+</script>
+
+<p>{count}</p>