```

feat(workflow): 完善工作流草稿保存功能并优化数据库查询

- 添加事务处理确保数据一致性
- 集成流程模板查询和验证逻辑
- 实现流程实例创建和开始节点初始化
- 添加工作项记录并优化SQL查询结构
- 改进错误处理机制
```

OpenAuth.App/workflow/WorkflowEngineApp.cs

@@ -648,9 +648,9 @@ public class WorkflowEngineApp : SqlSugarBaseApp<SysCategoryType, SugarDbContext
             .Select(zy => zy.NodeId)
             // 执行查询，返回 List<long> 结果
             .ToList();
-        
-        var allQuery = _sqlSugar.Queryable<IllegalConstructionAssessment, ZyFlowInstance, ZyFlowNode>(
-                (t, i, n) => new JoinQueryInfos(
+
+        var allQuery = _sqlSugar.Queryable<IllegalConstructionAssessment, ZyFlowInstance, ZyFlowNode>((t, i, n) =>
+                new JoinQueryInfos(
                     // 第一个左联：t(违建表) LEFT JOIN i(流程实例表) ON 业务编号匹配
                     JoinType.Left, t.BusinessNumber == i.BusinessNo,
                     // 第二个左联：i(流程实例表) LEFT JOIN n(流程节点表) ON 当前节点ID匹配
@@ -665,8 +665,9 @@ public class WorkflowEngineApp : SqlSugarBaseApp<SysCategoryType, SugarDbContext
                         // 子查询过滤条件：仅修改Contains + 加nodeIdList非空判断
                         .Where(w => w.HandlerId == userId)
                         // 关键1：用WhereIF判断列表非空，避免IN()语法错误；用SqlFunc.Contains替代原生Contains
-                        .WhereIF(nodeIdList != null && nodeIdList.Any(), 
-                            w => w.HandlerId == null && w.Status == "ToDo" && SqlFunc.ContainsArray(nodeIdList, w.NodeId))
+                        .WhereIF(nodeIdList != null && nodeIdList.Any(),
+                            w => w.HandlerId == null && w.Status == "ToDo" &&
+                                 SqlFunc.ContainsArray(nodeIdList, w.NodeId))
                         // 主查询与子查询的实例ID关联（原有逻辑，不变）
                         .Where(w => w.InstanceId == i.InstanceId)
                         .Select(w => w.InstanceId)
@@ -1002,25 +1003,73 @@ public class WorkflowEngineApp : SqlSugarBaseApp<SysCategoryType, SugarDbContext
     /// <exception cref="NotImplementedException"></exception>
     public object SaveDraft(InitiateFlowRequestDto requestDto)
     {
-        requestDto.BusinessNo = _businessNoGenerator.GenerateBusinessNo("WF");
-        var attachmentPaths = string.Join(",", requestDto.Attachments);
-        var user = _auth.GetCurrentUser().User;
-        var illegalConstructionAssessment = new IllegalConstructionAssessment
+        try
         {
-            Id = requestDto.BusinessNo,
-            Title = requestDto.Title,
-            BusinessNumber = requestDto.BusinessNo,
-            Attachments = requestDto.Attachments != null ? attachmentPaths : string.Empty,
-            AcceptanceTime = DateTime.Now,
-            Status = "Draft",
-            Type = requestDto.type,
-            CreateTime = DateTime.Now,
-            CreateUser = user.Name,
-            UpdateTime = DateTime.Now,
-            CreateUserId = user.Id
-        };
-        _sqlSugar.Insertable(illegalConstructionAssessment).ExecuteCommand();
-        return true;
+            UnitWork.Db.Ado.BeginTran();
+            requestDto.BusinessNo = _businessNoGenerator.GenerateBusinessNo("WF");
+            var attachmentPaths = string.Join(",", requestDto.Attachments);
+            var user = _auth.GetCurrentUser().User;
+            var illegalConstructionAssessment = new IllegalConstructionAssessment
+            {
+                Id = requestDto.BusinessNo,
+                Title = requestDto.Title,
+                BusinessNumber = requestDto.BusinessNo,
+                Attachments = requestDto.Attachments != null ? attachmentPaths : string.Empty,
+                AcceptanceTime = DateTime.Now,
+                Status = "Draft",
+                Type = requestDto.type,
+                CreateTime = DateTime.Now,
+                CreateUser = user.Name,
+                UpdateTime = DateTime.Now,
+                CreateUserId = user.Id
+            };
+            _sqlSugar.Insertable(illegalConstructionAssessment).ExecuteCommand();
+            var template = _sqlSugar.Queryable<ZyFlowTemplate>()
+                .Where(t => t.FlowCode == requestDto.FlowCode && t.IsEnabled == true)
+                .First();
+            if (template == null)
+                throw new Exception($"流程模板【{requestDto.FlowCode}】不存在或未启用");
+
+            // 步骤2：查询流程开始节点（区县提交）
+            var startNode = _sqlSugar.Queryable<ZyFlowNode>()
+                .Where(n => n.TemplateId == template.TemplateId && n.NodeType == "Start" && n.NodeName == "区县提交")
+                .First();
+            if (startNode == null)
+                throw new Exception("流程开始节点【区县提交】不存在，请配置节点");
+            var flowInstance = new ZyFlowInstance
+            {
+                TemplateId = template.TemplateId,
+                FlowCode = template.FlowCode,
+                BusinessNo = requestDto.BusinessNo,
+                Status = "Draft", // 已提交
+                CurrentNodeId = startNode.NodeId,
+                InitiatorId = user.Id,
+                InitiatorName = user.Name,
+                CreateTime = DateTime.Now
+            };
+            var instanceId = _sqlSugar.Insertable(flowInstance).ExecuteReturnIdentity();
+            // 步骤4：插入开始节点工作项（直接标记为已完成）
+            // 开始节点无ToDo
+            var startWorkitem = new ZyFlowWorkitem
+            {
+                InstanceId = instanceId,
+                NodeId = startNode.NodeId,
+                NodeName = startNode.NodeName,
+                HandlerId = user.Id,
+                HandlerName = user.Name,
+                Status = "Draft", // 已完成
+                ReceiveTime = DateTime.Now,
+                HandleTime = DateTime.Now,
+                Comment = "区县拟办"
+            };
+            _sqlSugar.Insertable(startWorkitem).ExecuteCommand();
+            UnitWork.Db.Ado.CommitTran();
+            return true;
+        }
+        finally
+        {
+            UnitWork.Db.Ado.RollbackTran();
+        }
     }
 
     public dynamic Detail(string businessNo)