[cm/signed/] with SLH-DSA-SHAKE-256s with Merkle-tree hashing.
[cm/pub/slh-dsa-shake-256s] public keys are used.

It is similar to [cm/signed/slh-dsa-shake-256s], but
[cm/hashed/shake-merkle] SHAKE256 Merkle-tree hashing is used.

Its /sigs/*/sign contents:
    sign-slh-dsa-shake-256s {
        {field . {map}}
        {field a {str} =slh-dsa-shake-256s}
        {field v {bin} len=29792}
    }
    
    sign-slh-dsa-shake-256s-ph {
        {field . {map}}
        {field a {str} =slh-dsa-shake-256s-ph}
        {field v {bin} len=29792}
    }
    
    sign-slh-dsa-shake-256s-ph {
        {field . {map}}
        {field a {str} =slh-dsa-shake-256s-merkle}
        {field v {bin} len=29792}
    }