修改agent流程，分步构建cdsl

backend/app/models/contracts.py

@@ -28,42 +28,3 @@ class ChatRequest(BaseModel):
 
 class ConversationPatch(BaseModel):
     current_task_id: str | None = None
-
-
-class ParameterUpdate(BaseModel):
-    values: dict[str, float] = Field(default_factory=dict)
-
-
-class ModifyRequest(BaseModel):
-    operation: str
-    selection: dict[str, Any] = Field(default_factory=dict)
-    parameters: dict[str, Any] = Field(default_factory=dict)
-
-
-class TaskArtifact(BaseModel):
-    path: str
-    role: str
-    kind: str
-
-
-class CadResult(BaseModel):
-    task_id: str
-    revision_id: str
-    cdsl_path: str
-    step_path: str
-    glb_path: str
-    report_path: str
-    parameters_path: str | None = None
-    selector_path: str | None = None
-    edges_path: str | None = None
-    topology_path: str | None = None
-    summary: str
-    reference_ids: list[str] = Field(default_factory=list)
-    engine: str = "cdsl_only"
-    quality_status: str = ""
-    quality_path: str | None = None
-    assumptions: list[str] = Field(default_factory=list)
-    warnings: list[str] = Field(default_factory=list)
-    repair_attempts: int = 0
-    snapshot_paths: list[str] = Field(default_factory=list)
-    snapshot_status: str = "unavailable"