Rebrand to Sage & Cream identity, working contact form, drop Firebase

- New sage/cream palette and stacked logo lockup (The Vine over Coffeehouse
  + Bakery) driven by currentColor; logo SVGs now colorable
- Reuse the logo component for the hero and section marks
- Rewrite site copy: real founding (Morissa Bennett, 2024), real story from
  the product range, remove invented claims and AI phrasing
- Contact form now sends over SMTP via /api/contact (nodemailer) with real
  send/error states, server-side validation, and reply-to the customer;
  delivers to CONTACT_TO. Add .env.example and a test-email script
- Fix mobile: unmount the off-screen menu (killed sideways scroll), cap logo
  width, responsive heroes and type
- Remove Firebase (config, tracked build output, placeholder pages, nix
  firebase-tools) now that hosting has moved
- Delete dead code: LoyaltyCardForm, ProductModal, LoadingSpinner, card-flip
  CSS, unused Playfair font
- Serve dev/start on port 2024

src/app/api/contact/route.ts

@@ -0,0 +1,57 @@
+import { NextResponse } from 'next/server';
+import nodemailer from 'nodemailer';
+
+// Server-side only, so the SMTP credentials never reach the browser.
+const { SMTP_SERVER, SMTP_PORT, SMTP_USERNAME, SMTP_TOKEN, CONTACT_TO, CONTACT_FROM } = process.env;
+
+export async function POST(request: Request) {
+  if (!SMTP_SERVER || !SMTP_PORT || !SMTP_USERNAME || !SMTP_TOKEN) {
+    console.error('contact: SMTP env vars missing');
+    return NextResponse.json({ error: 'Email is not configured.' }, { status: 500 });
+  }
+
+  let body: { name?: string; email?: string; message?: string };
+  try {
+    body = await request.json();
+  } catch {
+    return NextResponse.json({ error: 'Invalid request.' }, { status: 400 });
+  }
+
+  const name = body.name?.trim();
+  const email = body.email?.trim();
+  const message = body.message?.trim();
+
+  // Trust boundary: validate before handing anything to the mailer.
+  if (!name || !email || !message) {
+    return NextResponse.json({ error: 'Please fill in every field.' }, { status: 400 });
+  }
+  if (!/^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(email)) {
+    return NextResponse.json({ error: 'That email address does not look right.' }, { status: 400 });
+  }
+  if (message.length > 5000) {
+    return NextResponse.json({ error: 'That message is too long.' }, { status: 400 });
+  }
+
+  const port = Number(SMTP_PORT);
+  const transporter = nodemailer.createTransport({
+    host: SMTP_SERVER,
+    port,
+    secure: port === 465, // 465 is implicit TLS; 587 upgrades via STARTTLS
+    auth: { user: SMTP_USERNAME, pass: SMTP_TOKEN },
+  });
+
+  try {
+    await transporter.sendMail({
+      from: CONTACT_FROM || SMTP_USERNAME,
+      to: CONTACT_TO || '[email protected]',
+      replyTo: `${name} <${email}>`, // so hitting reply answers the customer
+      subject: `Website enquiry from ${name}`,
+      text: `${message}\n\nFrom: ${name} <${email}>`,
+    });
+  } catch (err) {
+    console.error('contact: send failed', err);
+    return NextResponse.json({ error: 'Could not send the message.' }, { status: 502 });
+  }
+
+  return NextResponse.json({ ok: true });
+}