use crateState;
use PersistenceError;
/// Trait for serializing and deserializing state
///
/// Serializers are used by checkpointers to save and load state.
/// JSON-based serializer using serde_json
///
/// This is the default serializer, similar to Python's JsonPlusSerializer.
/// It handles common types including LangChain primitives.
;
// Note: Serializer implementation is done per-state-type
// This avoids the unconstrained type parameter issue