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/api/auth/change-password/route.ts

@@ -0,0 +1,34 @@
+import { NextRequest, NextResponse } from "next/server";
+import { z } from "zod";
+import { getCurrentUserId } from "@/lib/session";
+import { changeUserPassword } from "@/lib/users";
+
+const changePasswordSchema = z.object({
+  currentPassword: z.string().min(1),
+  newPassword: z.string().min(6, "Das neue Passwort muss mindestens 6 Zeichen lang sein."),
+});
+
+export async function POST(request: NextRequest) {
+  const userId = await getCurrentUserId();
+  if (!userId) {
+    return NextResponse.json({ error: "Nicht authentifiziert." }, { status: 401 });
+  }
+
+  const body = await request.json();
+  const parsed = changePasswordSchema.safeParse(body);
+  if (!parsed.success) {
+    const message = parsed.error.issues[0]?.message ?? "Ungueltige Eingabe.";
+    return NextResponse.json({ error: message }, { status: 400 });
+  }
+
+  try {
+    await changeUserPassword(userId, parsed.data.currentPassword, parsed.data.newPassword);
+  } catch (e) {
+    return NextResponse.json(
+      { error: e instanceof Error ? e.message : "Passwort aendern fehlgeschlagen." },
+      { status: 400 }
+    );
+  }
+
+  return NextResponse.json({ ok: true });
+}