统一AssignmentStatus字段类型，新建枚举，对应状态

QYZH.InteractiveMagazine.Models/Enum/AssignmentStatusEnum.cs

@@ -0,0 +1,22 @@
+using System.ComponentModel;
+
+namespace QYZH.InteractiveMagazine.Models.Enum
+{
+    /// <summary>
+    /// 作业分配审核状态枚举: 0-未审核 1-已审核
+    /// </summary>
+    public enum AssignmentStatusEnum
+    {
+        /// <summary>
+        /// 未审核
+        /// </summary>
+        [Description("未审核")]
+        UnAssignmented = 0,
+
+        /// <summary>
+        /// 已审核
+        /// </summary>
+        [Description("已审核")]
+        Assignmented = 1
+    }    
+}