This is a follow-up for #16322

PlatformMerkleStateRoot extends MerkleStateRoot but it shouldn't really be the case because it unnecessarily creates a dependency on the implementation of the com.swirlds.state.State interface.
What we do need is an implementation of com.swirlds.platform.system.SwirldState that contains an instance of the com.swirlds.state.State and instance of com.swirlds.platform.state.MerkleStateLifecycles. Then, it should have the implementation of SwirldState interface methods that looks as follows:

    void preHandle(final Event event) {
        lifecycles.onPreHandle(event, state);
    }

    void handleConsensusRound(final Round round, final PlatformStateModifier platformState) {
         throwIfImmutable();
         lifecycles.onHandleConsensusRound(round, this);
    }

    void sealConsensusRound(@NonNull final Round round) {
            requireNonNull(round);
            throwIfImmutable();
           lifecycles.onSealConsensusRound(round, state);
    }

and so on. Then this implementation should replace usages of PlatformMerkleStateRoot, and PlatformMerkleStateRoot, in its turn, should be removed.

This refactoring will allow to get rid of swirlds-state-impl dependency. The common wisdom is that whilst app can depend on the implementation details of the state (and therefore the module), the platform has absolutely to reason for this dependency.