MedianCheck waits for availability of all exchange rates from the denom accept list, records historical stamp data based on the oracle params, computes the median/median deviation and then compares that to the data in the median/median deviation gRPC query.

NewChainHeight returns a new ChainHeight struct that starts a new goroutine subscribed to EventNewBlockHeader.

ChainHeight is used to cache the chain height of the current node which is being updated each time the node sends an event of EventNewBlockHeader.