test: add TS types

tests/DataTableBatchSelection.test.svelte

@@ -0,0 +1,29 @@
+<script lang="ts">
+  import { DataTable } from "../types";
+
+  const headers = [
+    { key: "name", value: "Name" },
+    { key: "port", value: "Port" },
+    { key: "rule", value: "Rule" },
+  ];
+
+  const rows = [
+    { id: "a", name: "Load Balancer 3", port: 3000, rule: "Round robin" },
+    { id: "b", name: "Load Balancer 1", port: 443, rule: "Round robin" },
+    { id: "c", name: "Load Balancer 2", port: 80, rule: "DNS delegation" },
+    { id: "d", name: "Load Balancer 6", port: 3000, rule: "Round robin" },
+    { id: "e", name: "Load Balancer 4", port: 443, rule: "Round robin" },
+    { id: "f", name: "Load Balancer 5", port: 80, rule: "DNS delegation" },
+  ];
+
+  let selectedRowIds = [rows[0].id, rows[1].id];
+
+  $: console.log("selectedRowIds", selectedRowIds);
+</script>
+
+<DataTable
+  batchSelection
+  bind:selectedRowIds
+  headers="{headers}"
+  rows="{rows}"
+/>