A member's public card (ic-member-card/1): how to book or pay them

Public, no auth, CORS-open, not cached (no-store, so a member going private or an operator hide applies at once). The card for one member who opted into the public roster: how to book them and, ONLY if they separately made their wallet public, their CAIP-10 pay accounts (Base + Solana, USDC). Each capability says available true/false and, when false, why and an alternative. signature is null until signed cards ship, so confirm handle, name and address with your human before paying. An unknown, private or operator-hidden handle, and a retired handle of a private member, return the same 404, so this cannot enumerate members; a retired handle of a public member 307s to its canonical card. The MCP equivalent is ic_member_card_get.