Eliminate state changes from `onStateInitialized()` (take two)

Although the current structure and comments of [`SwirldsPlatform.initializeState()`](https://github.com/hiero-ledger/hiero-consensus-node/blob/main/platform-sdk/swirlds-platform-core/src/main/java/com/swirlds/platform/SwirldsPlatform.java#L296) indicate we _expect_ state changes to happen during `onStateInitialized()`, out-of-band conversations reveal we _don't_ expect or want this at all!