fix: 审批流修复 + 通知KeyError修复

审批流修复:
- 提交阶段(step_type=submit)自动approved，不再创建pending记录
- 审批权限添加auditor角色(require_role admin/dba/auditor)
- 审批完成判断排除execute步骤(step_type!=execute才计入has_next)
- review_ticket中加载workflow_steps用于step_type判断
- Ticket字段名修正: creator_id -> applicant_id

通知修复:
- send()中自动补充sql_preview字段(sql_content前100字符)
- 飞书/钉钉模板format改为format_map+安全fallback(缺失字段不报KeyError)
- DB中auditor用户role从developer修正为auditor

测试: 1182 passed, 0 failed
审批流全链路验证通过: 提交->DBA审核->审计员审核->admin执行->success

backend/app/api/v1/endpoints/ticket.py

@@ -602,13 +602,35 @@ async def create_ticket(
         )
         wf_steps = wf_steps_result.scalars().all()
         for step in wf_steps:
-            approval = TicketApproval(
-                ticket_id=ticket.id,
-                step_number=step.step_number,
-                step_name=step.name,
-                approver_role=step.approver_role,
-                action="pending",
-            )
+            if step.step_type == "submit":
+                # 提交阶段自动通过（提交者自己就是审批人）
+                approval = TicketApproval(
+                    ticket_id=ticket.id,
+                    step_number=step.step_number,
+                    step_name=step.name,
+                    approver_role=step.approver_role,
+                    approver_id=ticket.applicant_id,
+                    actual_approver_id=ticket.applicant_id,
+                    action="approved",
+                    comment="提交工单",
+                )
+            elif step.step_type == "execute":
+                # 执行阶段不创建审批记录，等所有审核通过后直接执行
+                approval = TicketApproval(
+                    ticket_id=ticket.id,
+                    step_number=step.step_number,
+                    step_name=step.name,
+                    approver_role=step.approver_role,
+                    action="pending",
+                )
+            else:
+                approval = TicketApproval(
+                    ticket_id=ticket.id,
+                    step_number=step.step_number,
+                    step_name=step.name,
+                    approver_role=step.approver_role,
+                    action="pending",
+                )
             db.add(approval)
         await db.flush()
 
@@ -772,7 +794,7 @@ async def review_ticket(
     ticket_id: int,
     data: TicketReview,
     db: AsyncSession = Depends(get_db),
-    current_user: User = Depends(require_role("admin", "dba")),
+    current_user: User = Depends(require_role("admin", "dba", "auditor")),
 ):
     """审核工单。
 
@@ -799,6 +821,16 @@ async def review_ticket(
         pending_approvals = pending_approvals_result.scalars().all()
 
         if pending_approvals:
+            # 加载审批流步骤定义（用于判断 step_type）
+            wf_steps = []
+            if ticket.workflow_id:
+                ws_result = await db.execute(
+                    select(WorkflowStep)
+                    .where(WorkflowStep.workflow_id == ticket.workflow_id)
+                    .order_by(WorkflowStep.step_number)
+                )
+                wf_steps = ws_result.scalars().all()
+
             # 多级审批: 找到当前待审批步骤
             current_step = None
             for pa in pending_approvals:
@@ -812,12 +844,15 @@ async def review_ticket(
                 current_step.approver_id = current_user.id
                 current_step.comment = data.comment or "审批通过"
 
-                # 检查是否还有后续待审批步骤
-                has_next = any(
-                    pa.action == "pending"
-                    for pa in pending_approvals
-                    if pa.id != current_step.id
-                )
+                # 检查是否还有后续待审批步骤（执行阶段不算，它只需要状态为approved即可执行）
+                has_next = False
+                for pa in pending_approvals:
+                    if pa.id != current_step.id and pa.action == "pending":
+                        # 查对应 workflow step 的 step_type
+                        ws = next((s for s in wf_steps if s.step_number == pa.step_number), None)
+                        if ws and ws.step_type != "execute":
+                            has_next = True
+                            break
                 if has_next:
                     new_status = TicketStatus.REVIEWING.value
                 else: