fix: task-4 review round 1 (soon-constant, computed status, id guard)

app/page.tsx

@@ -2,7 +2,7 @@ import Link from "next/link";
 import { Suspense } from "react";
 import { getDb } from "@/lib/db";
 import { getVoucherStatus } from "@/lib/voucher-status";
-import { formatEuro } from "@/lib/vouchers";
+import { formatEuro, isExpiringSoon } from "@/lib/vouchers";
 
 const FILTERS = [
   { key: "", label: "Alle" },
@@ -28,14 +28,11 @@ function Skeleton() {
 async function VoucherList({ filter }: { filter: string }) {
   const db = getDb();
   const all = await db.voucher.findMany({ orderBy: { createdAt: "desc" } });
-  const now = Date.now();
-  const in14d = now + 14 * 24 * 3600 * 1000;
   const filtered = all.filter((v) => {
     const s = getVoucherStatus(v);
     if (filter === "eingeloest") return s === "eingeloest";
     if (filter === "abgelaufen") return s === "abgelaufen";
-    if (filter === "bald")
-      return s === "aktiv" && v.ablaufdatum && +new Date(v.ablaufdatum) >= now && +new Date(v.ablaufdatum) <= in14d;
+    if (filter === "bald") return s === "aktiv" && isExpiringSoon(v.ablaufdatum);
     if (filter === "aktiv") return s === "aktiv";
     return true;
   });