create Or Get Data Store
protected fun createOrGetDataStore(migrations: List<ERROR CLASS: Symbol not found for DataMigration<ERROR CLASS: Symbol not found for Preferences>> = emptyList()): ERROR CLASS: Symbol not found for DataStore<ERROR CLASS: Symbol not found for Preferences>
Helper to create or return an existing DataStore with proper scope management for a given filename.
All subclasses MUST use this method instead of PreferenceDataStoreFactory.create() directly to ensure the DataStore is created with the provider's coroutine scope.
This is critical for proper lifecycle management and cleanup during shutdownAllDataStores.