Namespace Demo Brings ENSv2 Subnames Fully Onchain

Namespace launches ENSv2-compatible onchain subnames demo. Test at app.ens.dev, then demo.namespace.ninja. Activations, pricing, minting are fully onchain via subregistries—no NameWrapper or fuses. Adds multi-token gates, USD pricing, expirable subnames. Uses Sepolia registry 0xBDC85dD5b15D7ecb354cd7cb6f2c50b4f2c4F0E2. Audits pending. Feedback requested.