DomainConfig

struct DomainConfig {
    /// @notice Maximum fee (in USDC units) payable to CCTP for a burn toward this domain.
    uint256 maxFee;
    /// @notice Minimum finality threshold before Iris attests (e.g. 1000 fast / 2000 standard-finalized).
    uint32 minFinalityThreshold;
    /// @notice Destination caller lock (`bytes32(0)` = permissionless mint). Optional for plain burns, but
    ///         REQUIRED for Lattice hooked burns: set it to the destination diamond, or {depositForBurnWithHook}
    ///         reverts {ICCTPBridgeAdapter-CCTPHookWithoutDestinationCaller}. It is per domain, so once set, plain
    ///         burns to the domain are also receivable only through the destination diamond's relay.
    bytes32 destinationCaller;
}