add day 79 (finally object reactive data)

day79/src/entry-client.ts

@@ -0,0 +1,12 @@
+import { renderPage } from './lib/router/pageRenderer';
+
+await import('./style.css');
+await renderPage();
+
+window.onpopstate = async e => {
+	if (e.state === null) {
+		return;
+	}
+
+	await renderPage();
+};