add test

packages/svelte/tests/runtime-runes/samples/hydrate-modified-input-group/_config.js

@@ -0,0 +1,18 @@
+import { test } from '../../test';
+
+export default test({
+	skip_mode: ['client'],
+
+	test({ assert, target, hydrate }) {
+		const inputs = /** @type {NodeListOf<HTMLInputElement>} */ (target.querySelectorAll('input'));
+		inputs[1].checked = true;
+		inputs[1].dispatchEvent(new window.Event('change'));
+		// Hydration shouldn't reset the value to 1
+		hydrate();
+
+		assert.htmlEqual(
+			target.innerHTML,
+			'<input type="radio" value="1"><input type="radio" value="2"><input type="radio" value="3">\n2'
+		);
+	}
+});

packages/svelte/tests/runtime-runes/samples/hydrate-modified-input-group/main.svelte

@@ -0,0 +1,9 @@
+<script>
+	let value = $state(1);
+</script>
+
+{#each [1, 2, 3] as number}
+	<input type="radio" value={number} bind:group={value}>
+{/each}
+
+{value}