Validates a candidate app payload against current launch requirements before any transaction is sent.
app.elata.bio/api.SIWE-issued JWT, scoped to a wallet address. Obtain via Sign-In With
Ethereum (EIP-4361) against app.elata.bio. Required for personalized
Portfolio and Rewards endpoints. The sub claim is the wallet address;
a request whose path {address} does not match the sub is rejected.