feat: Next.js + Tailwind + shadcn/ui project skeleton

- create-next-app with TypeScript, App Router, Tailwind CSS
- shadcn/ui initialized with defaults (button component + utils)
- .env.example with DATABASE_URL and SESSION_SECRET placeholders
- README.md with docs/runbooks/ reference

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

next.config.ts

@@ -0,0 +1,7 @@
+import type { NextConfig } from "next";
+
+const nextConfig: NextConfig = {
+  /* config options here */
+};
+
+export default nextConfig;