IsMarketUpdateTx returns `true` if the supplied `tx` consists of a single MsgUpdateMarkets or MsgUpsertMarkets.

NewValidateMarketUpdateDecorator returns an AnteDecorator that is able to check for x/marketmap update messages and reject them if they are updating cross margin markets.

ShouldSkipSequenceValidation returns whether sequence validation can be skipped for a given list of messages.

FreeInfiniteGasDecorator is an AnteHandler that sets `GasMeter` to `FreeInfiniteGasMeter` for off-chain single clob msg transactions, and app-injected transactions.

SigVerificationDecorator verifies all signatures for a tx and return an error if any are invalid.

ValidateMsgTypeDecorator checks that the tx has the expected message types.