Major rework: multi-user accounts (register/login, per-user data isolation), new layout with sidebar/dashboard/profile menu, matrix phase view with collapsible category columns, life timeline with ages per phase, live budget capping, collapsible transitions, mobile support

src/app/page.tsx

@@ -8,11 +8,21 @@ import type { HouseholdInput } from "@/lib/types";
 
 export default function Home() {
   const [household, setHousehold] = useState<HouseholdInput | null | undefined>(undefined);
+  const [username, setUsername] = useState<string>("");
 
   useEffect(() => {
-    api.get<{ household: HouseholdInput | null }>("/api/household").then((data) => {
-      setHousehold(data.household);
-    });
+    Promise.all([
+      api.get<{ household: HouseholdInput | null }>("/api/household"),
+      api.get<{ user: { username: string } }>("/api/auth/me"),
+    ])
+      .then(([householdData, meData]) => {
+        setUsername(meData.user.username);
+        setHousehold(householdData.household);
+      })
+      .catch(() => {
+        // Session abgelaufen/ungueltig -- Middleware leitet beim naechsten Request um.
+        window.location.href = "/login";
+      });
   }, []);
 
   if (household === undefined) {
@@ -27,5 +37,5 @@ export default function Home() {
     return <Onboarding onDone={setHousehold} />;
   }
 
-  return <AppShell initialHousehold={household} />;
+  return <AppShell initialHousehold={household} username={username} />;
 }