[gtag][s]: include google analytics utility functions

packages/portal/lib/gtag.ts

@@ -0,0 +1,19 @@
+export const GA_TRACKING_ID = 'G-NX72GYFHFS';
+
+//https://developers.google.com/analytics/devguides/collection/gtagjs/pages
+//eslint-disable-next-line @typescript-eslint/explicit-module-boundary-types
+export const pageview = (url: string) => {
+  window.gtag('config', GA_TRACKING_ID, {
+    page_path: url,
+  });
+};
+
+// https://developers.google.com/analytics/devguides/collection/gtagjs/events
+// eslint-disable-next-line @typescript-eslint/explicit-module-boundary-types
+export const event = ({ action, category, label, value }) => {
+  window.gtag('event', action, {
+    event_category: category,
+    event_label: label,
+    value: value,
+  });
+};