refactor(rewards): expand __init__ facade and fix SARMConfig __post_init__ crash

src/lerobot/rewards/__init__.py

@@ -13,9 +13,24 @@
 # limitations under the License.
 
 from .classifier.configuration_classifier import RewardClassifierConfig as RewardClassifierConfig
+from .factory import (
+    get_reward_model_class as get_reward_model_class,
+    make_reward_model as make_reward_model,
+    make_reward_model_config as make_reward_model_config,
+    make_reward_pre_post_processors as make_reward_pre_post_processors,
+)
+from .pretrained import PreTrainedRewardModel as PreTrainedRewardModel
 from .sarm.configuration_sarm import SARMConfig as SARMConfig
 
 __all__ = [
+    # Configuration classes
     "RewardClassifierConfig",
     "SARMConfig",
+    # Base class
+    "PreTrainedRewardModel",
+    # Factory functions
+    "get_reward_model_class",
+    "make_reward_model",
+    "make_reward_model_config",
+    "make_reward_pre_post_processors",
 ]

src/lerobot/rewards/sarm/configuration_sarm.py

@@ -108,8 +108,6 @@ class SARMConfig(RewardModelConfig):
     )
 
     def __post_init__(self):
-        super().__post_init__()
-
         if self.annotation_mode not in ["single_stage", "dense_only", "dual"]:
             raise ValueError(
                 f"annotation_mode must be 'single_stage', 'dense_only', or 'dual', got {self.annotation_mode}"