Add filters javascript

pkg/dashboard/assets/js/filter.js

@@ -0,0 +1,22 @@
+$(function () {
+
+  // Check selected namespace options on page load
+  const urlParams = new URLSearchParams(window.location.search);
+  const currentNamespaces = urlParams.getAll('ns');
+  currentNamespaces.forEach(ns => {
+    $(`input#namespace-${ns}`).prop('checked', true);
+  });
+
+  // Handle new filter submissions
+  $('#namespaceFiltersForm').on('submit', e => {
+    e.preventDefault();
+    let newParams = new URLSearchParams();
+    $('#namespaceFiltersForm input[type="checkbox"]').each((index, checkbox) => {
+      if (checkbox.checked) {
+        newParams.append('ns', checkbox.name);
+      }
+    });
+    window.location = new URL(`?${newParams.toString()}`, window.location).toString();
+  });
+});
+