Initial commit: dating app web frontend (Next.js)

Phone+OTP auth, staged onboarding, admin-approval-gated home screen,
and the full discovery/match/chat UI (swipe deck with drag gestures,
match modal, profile detail, filters, messages/chat) wired to the
real backend, styled after a Figma dating-app UI kit.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/app/(main)/layout.tsx

@@ -0,0 +1,35 @@
+"use client";
+
+import { ReactNode, useEffect } from "react";
+import { useRouter } from "next/navigation";
+import { useAuth } from "@/lib/auth-context";
+import { FullScreenLoader } from "@/components/ui/FullScreenLoader";
+import { BottomNav } from "@/components/BottomNav";
+import { stepByOrder } from "@/lib/onboarding-steps";
+
+export default function MainLayout({ children }: { children: ReactNode }) {
+  const router = useRouter();
+  const { status, user } = useAuth();
+
+  useEffect(() => {
+    if (status === "guest") {
+      router.replace("/login");
+      return;
+    }
+    if (status === "authenticated" && user && !user.is_onboarded) {
+      const slug = stepByOrder(user.current_step)?.slug ?? "basic-info";
+      router.replace(`/onboarding/${slug}`);
+    }
+  }, [status, user, router]);
+
+  if (status !== "authenticated" || !user?.is_onboarded) {
+    return <FullScreenLoader />;
+  }
+
+  return (
+    <div className="flex flex-col flex-1 min-h-dvh">
+      <div className="flex-1 overflow-y-auto">{children}</div>
+      <BottomNav />
+    </div>
+  );
+}