Fix chain mask list for slave-shard relationship

[ninjaahhh]

as of now our config is still using chain mask list to configure shard-slave mapping:

    """ Represent a mask of chains, basically matches all the bits from the right until the leftmost bit is hit.
    E.g.,
    mask = 1, matches *
    mask = 0b10, matches *0
    mask = 0b101, matches *01
    """

however it doesn't fit our current chain/shard ID decoding. we should migrate the chain mask list to be a list of full shard IDs indicating exactly what shards a slave should run.

[ninjaahhh]

@lyhe18 can you take this task?

[lyhe18]

No problem~

[lyhe18]

This issue is linked to #831