优化agent

backend/app/models/contracts.py

@@ -28,7 +28,6 @@ class ChatRequest(BaseModel):
 
 class ConversationPatch(BaseModel):
     current_task_id: str | None = None
-    attachments: list[dict[str, Any]] | None = None
 
 
 class ParameterUpdate(BaseModel):
@@ -57,8 +56,6 @@ class CadResult(BaseModel):
     parameters_path: str | None = None
     selector_path: str | None = None
     edges_path: str | None = None
-    design_intent_id: str | None = None
-    design_intent_path: str | None = None
     summary: str
     reference_ids: list[str] = Field(default_factory=list)
     engine: str = "cdsl_only"