feat: implement bff layer

app/api/books/[book]/route.ts

@@ -1,12 +1,12 @@
 import { NextResponse } from "next/server";
-import { prisma } from "@/lib/db";
+import { getBookMeta } from "@/lib/api";
 
 export async function GET(
   _req: Request,
-  { params }: { params: Promise<{ book: string }> }
+  { params }: { params: Promise<{ book: string }> },
 ) {
   const { book } = await params;
-  const meta = await prisma.bookMeta.findUnique({ where: { book } });
+  const meta = await getBookMeta(book);
   if (!meta) return NextResponse.json({ error: "Not found" }, { status: 404 });
-  return NextResponse.json({ book: meta.book, ...meta.data as Record<string, unknown> });
+  return NextResponse.json(meta);
 }