Feature: Add product selection when starting design from photo request

Added intermediate page (/admin/custom-requests/[id]/start-design) that
lets the admin choose which product to design the photo on. Shows the
photo request details and all available products with the originally
requested product pre-selected.

src/app/admin/custom-requests/[id]/page.tsx

@@ -18,10 +18,6 @@ export default async function CustomRequestDetailPage({ params }: { params: { id
   const whatsappDigits = request.customerPhone ? request.customerPhone.replace(/\D/g, '') : null;
   const whatsappMessage = `Hi ${request.customerName}, thanks for sending over your photo for a ${request.product.name} — we're working on it!`;
 
-  const designParams = new URLSearchParams({
-    customRequestId: request.id,
-  });
-
   return (
     <div className="mx-auto max-w-2xl px-6 py-12">
       <AdminNav />
@@ -61,7 +57,7 @@ export default async function CustomRequestDetailPage({ params }: { params: { id
         <DownloadPhotoButton photoUrl={request.imageDataUrl} customerName={request.customerName} />
 
         <Link
-          href={`/made-to-order/${request.product.slug}?${designParams.toString()}`}
+          href={`/admin/custom-requests/${request.id}/start-design`}
           className="bg-clay px-6 py-3 text-sm font-medium text-paper hover:bg-clay-dark"
         >
           Start a design for this

src/app/admin/custom-requests/[id]/start-design/page.tsx

@@ -0,0 +1,77 @@
+import { notFound, redirect } from 'next/navigation';
+import { prisma } from '@/lib/prisma';
+import AdminNav from '@/components/AdminNav';
+
+export default async function StartDesignPage({ params }: { params: { id: string } }) {
+  const request = await prisma.customRequest.findUnique({
+    where: { id: params.id },
+    include: { product: true },
+  });
+  if (!request) notFound();
+
+  const products = await prisma.product.findMany({
+    where: { showOnPersonalised: true },
+    orderBy: { name: 'asc' },
+  });
+
+  const handleSubmit = async (formData: FormData) => {
+    'use server';
+    const productId = String(formData.get('productId') ?? '');
+    const product = await prisma.product.findUnique({ where: { id: productId } });
+    if (product) {
+      redirect(`/made-to-order/${product.slug}?customRequestId=${request.id}`);
+    }
+  };
+
+  return (
+    <div className="mx-auto max-w-2xl px-6 py-12">
+      <AdminNav />
+      <h1 className="font-display text-3xl">Start design for this photo</h1>
+      <p className="mt-2 text-sm text-muted">Select which product to design this photo on</p>
+
+      <div className="mt-6 border border-line bg-surface p-6">
+        <img src={request.imageDataUrl} alt="Customer's photo" className="mx-auto max-h-64 object-contain" />
+      </div>
+
+      <div className="mt-6 border border-line bg-surface p-6">
+        <p className="tag-label mb-2">Photo request details</p>
+        <p className="text-sm mb-2"><span className="font-medium">Customer:</span> {request.customerName}</p>
+        <p className="text-sm"><span className="font-medium">Originally requested for:</span> {request.product.name}</p>
+      </div>
+
+      <form action={handleSubmit} className="mt-6 space-y-4 border border-line bg-surface p-6">
+        <div>
+          <label htmlFor="productId" className="tag-label mb-2 block">
+            Which product to design on?
+          </label>
+          <select
+            id="productId"
+            name="productId"
+            required
+            defaultValue={request.productId}
+            className="w-full border border-line bg-paper px-3 py-2 text-sm"
+          >
+            <option value="">Select a product...</option>
+            {products.map((p) => (
+              <option key={p.id} value={p.id}>
+                {p.name}
+              </option>
+            ))}
+          </select>
+        </div>
+
+        <div className="flex gap-3 pt-4">
+          <button type="submit" className="bg-clay px-6 py-3 text-sm font-medium text-paper hover:bg-clay-dark">
+            Go to design canvas
+          </button>
+          <a
+            href={`/admin/custom-requests/${request.id}`}
+            className="border border-line px-6 py-3 text-sm hover:border-clay hover:text-clay"
+          >
+            Cancel
+          </a>
+        </div>
+      </form>
+    </div>
+  );
+}