fix(admin): persist data directory and pass env vars

app/api/admin/contact/[id]/route.ts

@@ -0,0 +1,19 @@
+import { NextResponse } from "next/server";
+import { requireAdminSession } from "@/lib/admin/auth";
+import { updateContactStatus } from "@/lib/admin/store";
+import type { InquiryStatus } from "@/lib/admin/types";
+
+const statuses: InquiryStatus[] = ["new", "in_progress", "done"];
+
+export async function PATCH(request: Request, { params }: { params: Promise<{ id: string }> }) {
+  if (!await requireAdminSession()) return NextResponse.json({ message: "Nicht autorisiert." }, { status: 401 });
+
+  const body = await request.json() as { status?: InquiryStatus };
+  if (!body.status || !statuses.includes(body.status)) {
+    return NextResponse.json({ message: "Ungültiger Status." }, { status: 400 });
+  }
+
+  const { id } = await params;
+  await updateContactStatus(id, body.status);
+  return NextResponse.json({ message: "Status aktualisiert." });
+}