Fix Task config and callback parameters being silently ignored

- Preserve config dictionary in process_config function instead of removing it
- Only set Task attributes for valid model fields in set_attributes_based_on_config
- Add comprehensive tests for config retention, value extraction, and callback retention
- Add reproduction script demonstrating the fix for issue #3160
- Fix deprecation warning by using class.model_fields instead of instance.model_fields

Fixes #3160

Co-Authored-By: Jo\u00E3o <joao@crewai.com>

src/crewai/task.py

@@ -324,7 +324,8 @@ class Task(BaseModel):
         """Set attributes based on the agent configuration."""
         if self.config:
             for key, value in self.config.items():
-                setattr(self, key, value)
+                if key in self.__class__.model_fields:
+                    setattr(self, key, value)
         return self
 
     @model_validator(mode="after")

src/crewai/utilities/config.py

@@ -34,6 +34,4 @@ def process_config(
         else:
             values[key] = value
 
-    # Remove the config from values to avoid duplicate processing
-    values.pop("config", None)
     return values