Migrate policy to PolicyProcessorPipeline system

🤖 **Automated Policy Migration to PolicyProcessorPipeline**

This PR migrates your model to the new LeRobot policy format using the modern PolicyProcessorPipeline architecture.

## What Changed

### ✨ **New Architecture - PolicyProcessorPipeline**
Your model now uses external PolicyProcessorPipeline components for data processing instead of built-in normalization layers. This provides:
- **Modularity**: Separate preprocessing and postprocessing pipelines
- **Flexibility**: Easy to swap, configure, and debug processing steps
- **Compatibility**: Works with the latest LeRobot ecosystem

### 🔧 **Normalization Extraction**
We've extracted normalization statistics from your model's state_dict and removed the built-in normalization layers:
- **Extracted patterns**: `normalize_inputs.*`, `unnormalize_outputs.*`, `normalize.*`, `unnormalize.*`, `input_normalizer.*`, `output_normalizer.*`
- **Statistics preserved**: Mean, std, min, max values for all features
- **Clean model**: State dict now contains only core model weights

### 📦 **Files Added**
- **preprocessor_config.json**: Configuration for input preprocessing pipeline
- **postprocessor_config.json**: Configuration for output postprocessing pipeline
- **model.safetensors**: Clean model weights without normalization layers
- **config.json**: Updated model configuration
- **train_config.json**: Training configuration
- **README.md**: Updated model card with migration information

### 🚀 **Benefits**
- **Backward Compatible**: Your model behavior remains identical
- **Future Ready**: Compatible with latest LeRobot features and updates
- **Debuggable**: Easy to inspect and modify processing steps
- **Portable**: Processors can be shared and reused across models

### 💻 **Usage**
```python
# Load your migrated model
from lerobot.policies import get_policy_class
from lerobot.processor import PolicyProcessorPipeline

# The preprocessor and postprocessor are now external
preprocessor = PolicyProcessorPipeline.from_pretrained("your-model-repo", config_filename="preprocessor_config.json")
postprocessor = PolicyProcessorPipeline.from_pretrained("your-model-repo", config_filename="postprocessor_config.json")
policy = get_policy_class("your-policy-type").from_pretrained("your-model-repo")

# Process data through the pipeline
processed_batch = preprocessor(raw_batch)
action = policy(processed_batch)
final_action = postprocessor(action)
```

*Generated automatically by the LeRobot policy migration script*

README.md

@@ -6,8 +6,8 @@ license: apache-2.0
 model_name: smolvla
 pipeline_tag: robotics
 tags:
-- lerobot
 - smolvla
+- lerobot
 - robotics
 ---
 

config.json

@@ -8,7 +8,7 @@
                 6
             ]
         },
-        "observation.images.camera1": {
+        "observation.image2": {
             "type": "VISUAL",
             "shape": [
                 3,
@@ -16,7 +16,7 @@
                 256
             ]
         },
-        "observation.images.camera2": {
+        "observation.image": {
             "type": "VISUAL",
             "shape": [
                 3,
@@ -24,7 +24,7 @@
                 256
             ]
         },
-        "observation.camera3": {
+        "observation.image3": {
             "type": "VISUAL",
             "shape": [
                 3,

policy_postprocessor.json

@@ -1,13 +1,6 @@
 {
   "name": "policy_postprocessor",
   "steps": [
-    {
-      "registry_name": "device_processor",
-      "config": {
-        "device": "cpu",
-        "float_dtype": null
-      }
-    },
     {
       "registry_name": "unnormalizer_processor",
       "config": {
@@ -26,7 +19,14 @@
           "ACTION": "MEAN_STD"
         }
       },
-      "state_file": "policy_postprocessor_step_1_unnormalizer_processor.safetensors"
+      "state_file": "policy_postprocessor_step_0_unnormalizer_processor.safetensors"
+    },
+    {
+      "registry_name": "device_processor",
+      "config": {
+        "device": "cpu",
+        "float_dtype": null
+      }
     }
   ]
 }

policy_postprocessor_step_0_unnormalizer_processor.safetensors

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:490ab239d96e263687c0b2e386a0afbc235a2eceb9857c36ed32f2f162a3e7c8
+size 640