Major API changes:
- Migrate from `haiku` (deprecated) to `flax` as the base naural network library.
- Update agent names to match literature:
- QLearning (deep Q-learning) -> DQN,
- DQN (deep double Q-learning) -> DDQN.
- Move particle filter from `agents` to `utils`.
- New behavior of loggers - all declared loggers get values from all sources.
New functionalities:
- Add Weights & Biases logger.
Other important changes:
- Fix updates with empty replay buffer.
- Fix logging of arrays to TensorBoard.
- Minor improvements in documentation.
- Rewrite Gymnasium integration example in documentation.
- Improve the CCOD example to better reflect the original implementation.