feat: rebrand to Domain Scanner platform

Replace GeoExport static site with Next.js domain intelligence app:
real DNS/WHOIS/SSL/HTTP/geo scans, SSE progress, Docker stack,
updated install/uninstall scripts, and full documentation.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/app/api/health/route.ts

@@ -0,0 +1,11 @@
+import { NextResponse } from "next/server";
+import { prisma } from "@/lib/prisma";
+
+export async function GET() {
+  try {
+    await prisma.$queryRaw`SELECT 1`;
+    return NextResponse.json({ status: "ok", db: true });
+  } catch {
+    return NextResponse.json({ status: "degraded", db: false }, { status: 503 });
+  }
+}