Refactor `*ServiceMigrator` and `*SchemaRegistry` classes by extracting common logic

@tinker-michaelj suggested the following idea as a follow-up for https://github.com/hashgraph/hedera-services/pull/16379 :

> it would be nice at some point if we could extract the common logic between the OrderedServiceMigrator/MerkleSchemaRegistry and FakeServiceMigrator/FakeSchemaRegistry types and reduce duplication between the subprocess and embedded Hedera state lifecycles.

That is, the idea is to consider `OrderedServiceMigrator` / `FakeServiceMigrator` and `MerkleSchemaRegistry` / `FakeSchemaRegistry` pairs, extract common logic to a class that resides in `swirlds-state-impl`. This will help to reduce the logic duplication