Add Phase 0: sign-up, login, and profile

- Next.js (App Router) + TypeScript + Tailwind
- Prisma + SQLite for the User model
- Sign-up with 18+ age gate, email/password validation (zod), bcrypt hashing
- Login via NextAuth credentials provider, JWT sessions
- Protected /profile route (view + edit name/bio)

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VL5YUEf2B9LG4xdVUQwcSg

src/app/profile/page.tsx

@@ -0,0 +1,35 @@
+import { getServerSession } from "next-auth";
+import { redirect } from "next/navigation";
+import { authOptions } from "@/lib/auth";
+import { prisma } from "@/lib/prisma";
+import ProfileEditor from "./profile-editor";
+import SignOutButton from "./sign-out-button";
+
+export default async function ProfilePage() {
+  const session = await getServerSession(authOptions);
+  if (!session?.user?.id) {
+    redirect("/login");
+  }
+
+  const user = await prisma.user.findUnique({
+    where: { id: session.user.id },
+    select: { id: true, name: true, email: true, age: true, bio: true },
+  });
+
+  if (!user) {
+    redirect("/login");
+  }
+
+  return (
+    <main className="mx-auto flex min-h-screen max-w-sm flex-col justify-center gap-6 px-6 py-12">
+      <div className="flex items-center justify-between">
+        <h1 className="text-2xl font-bold text-brand">Your profile</h1>
+        <SignOutButton />
+      </div>
+      <p className="text-sm text-gray-500">
+        {user.email} &middot; Age {user.age}
+      </p>
+      <ProfileEditor initialName={user.name} initialBio={user.bio} />
+    </main>
+  );
+}