First working prototype

src/lib/router.svelte.js

@@ -0,0 +1,29 @@
+/**
+ * Three screens, so no router dependency — just enough hash handling that the
+ * Android back button behaves inside an installed PWA.
+ *
+ * `route === null` means "wherever the day state says", which is the default the
+ * worker should land on.
+ */
+
+const ROUTES = ['resume', 'today', 'settings'];
+
+function fromHash() {
+  const h = location.hash.replace(/^#\/?/, '');
+  return ROUTES.includes(h) ? h : null;
+}
+
+export const router = $state({ route: fromHash() });
+
+window.addEventListener('hashchange', () => {
+  router.route = fromHash();
+});
+
+export function go(route) {
+  location.hash = route ? `#/${route}` : '';
+}
+
+export function back() {
+  if (history.length > 1) history.back();
+  else go(null);
+}