This example uses a TICKET_VALID attestation as an event ticket. On purchase,
an authorized issuer creates the attestation for the purchaser's Stellar address.
At venue check-in, the venue verifies the claim for that address and immediately
revokes the attestation, making the ticket single-use.
Attestations have no transfer entry point and their subject is immutable. A
different address therefore cannot use a ticket issued to the purchaser, avoiding
the bearer-token behavior that enables ticket resale and scalping.
Run the demonstration and its assertions with:
cargo test --example event_ticketing