Implement model (and some factor) coder with evolving (#52)

* store code into FBImplementation

* fix path related bugs

* fix a bug

* fix factor related small bugs

* re-submit all model related code

* new code to model coder

* finish the model evolving code

---------

Co-authored-by: xuyang1 <xuyang1@microsoft.com>

rdagent/components/coder/model_coder/CoSTEER/evolvable_subjects.py

@@ -0,0 +1,29 @@
+from rdagent.components.coder.model_coder.model import (
+    ModelExperiment,
+    ModelImplementation,
+    ModelTask,
+)
+from rdagent.core.evolving_framework import EvolvableSubjects
+from rdagent.core.log import RDAgentLog
+
+
+class ModelEvolvingItem(ModelExperiment, EvolvableSubjects):
+    """
+    Intermediate item of model implementation.
+    """
+
+    def __init__(
+        self,
+        sub_tasks: list[ModelTask],
+        sub_gt_implementations: list[ModelImplementation] = None,
+    ):
+        ModelExperiment.__init__(self, sub_tasks=sub_tasks)
+        if sub_gt_implementations is not None and len(
+            sub_gt_implementations,
+        ) != len(self.sub_tasks):
+            self.sub_gt_implementations = None
+            RDAgentLog().warning(
+                "The length of sub_gt_implementations is not equal to the length of sub_tasks, set sub_gt_implementations to None",
+            )
+        else:
+            self.sub_gt_implementations = sub_gt_implementations