Initial upload of BB-Apartment 2026 website.

Adds the complete Next.js website including i18n routing, house and
apartment pages, Beds24 v2 integration for live availability/pricing,
Stripe checkout, contact forms, Docker setup and deployment docs.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

src/lib/mail.ts

@@ -0,0 +1,63 @@
+import nodemailer from "nodemailer";
+
+export interface ContactMessage {
+  email: string;
+  message: string;
+  name?: string;
+  /** Optional context, e.g. the search dates that had no availability. */
+  context?: string;
+}
+
+function getTransport() {
+  const { SMTP_HOST, SMTP_PORT, SMTP_USER, SMTP_PASSWORD } = process.env;
+  if (!SMTP_HOST || !SMTP_USER || !SMTP_PASSWORD) {
+    return null;
+  }
+
+  return nodemailer.createTransport({
+    host: SMTP_HOST,
+    port: Number(SMTP_PORT) || 587,
+    secure: Number(SMTP_PORT) === 465,
+    auth: {
+      user: SMTP_USER,
+      pass: SMTP_PASSWORD,
+    },
+  });
+}
+
+export async function sendContactMessage(data: ContactMessage): Promise<void> {
+  const transport = getTransport();
+  const to = process.env.CONTACT_INBOX_EMAIL || "info@bb-apartment.de";
+  const from = process.env.SMTP_FROM || "noreply@bb-apartment.de";
+
+  const subject = `Neue Kontaktanfrage von ${data.name || data.email}`;
+  const text = [
+    data.context ? `Kontext: ${data.context}` : null,
+    `Name: ${data.name || "-"}`,
+    `E-Mail: ${data.email}`,
+    "",
+    data.message,
+  ]
+    .filter(Boolean)
+    .join("\n");
+
+  if (!transport) {
+    // No SMTP configured yet (development) — log instead of failing so the
+    // form still "works" locally.
+    console.log("[contact] SMTP not configured, would have sent:", {
+      to,
+      from,
+      subject,
+      text,
+    });
+    return;
+  }
+
+  await transport.sendMail({
+    to,
+    from,
+    replyTo: data.email,
+    subject,
+    text,
+  });
+}