feat: 完成input_context节点

app/exceptions.py

@@ -1,5 +1,22 @@
 class AppError(Exception):
-    """应用业务异常。"""
+    """应用业务异常"""
+
+
+class DecisionError(AppError):
+    """决策服务错误；仅暴露安全摘要及服务端追踪信息"""
+
+    def __init__(
+        self,
+        message: str,
+        *,
+        kind: str,
+        status: int | None = None,
+        request_id: str | None = None,
+    ):
+        self.kind = kind
+        self.status = status
+        self.request_id = request_id
+        super().__init__(message)
 
 
 class ImportProcessError(AppError):