feat：优化执行步骤

app/schemas/actions/__init__.py

@@ -7,6 +7,7 @@ from pydantic import Field
 from .add import AddAction
 from .base import ActionModel, BaseAction
 from .delete import DeleteAction
+from .layout import AlignAction, ArrangeAction, DistributeAction, SetLayoutAction
 from .move import MoveAction
 from .resize import ResizeAction
 from .update import UpdateAction
@@ -23,8 +24,29 @@ Action = Annotated[
     Field(discriminator="type"),
 ]
 
+# 模型可以提交的动作：前端协议 + 布局意图
+# 布局意图由后端展开成 move 和 resize，不会返回给前端
+AgentAction = Annotated[
+    AddAction
+    | DeleteAction
+    | MoveAction
+    | ResizeAction
+    | UpdateAction
+    | UpdateCanvasAction
+    | ArrangeAction
+    | AlignAction
+    | DistributeAction
+    | SetLayoutAction,
+    Field(discriminator="type"),
+]
+
 __all__ = [
     "Action",
+    "AgentAction",
+    "AlignAction",
+    "ArrangeAction",
+    "DistributeAction",
+    "SetLayoutAction",
     "ActionModel",
     "AddAction",
     "BaseAction",