feat: add intelligent support workflow

backend/apps/workitems/models.py

@@ -0,0 +1,87 @@
+import uuid
+
+from django.conf import settings
+from django.db import models
+from django.db.models import Q
+
+
+class WorkItemStatus(models.TextChoices):
+    ACTIVE = "active", "待处理"
+    COMPLETED = "completed", "已完成"
+    CANCELLED = "cancelled", "已取消"
+
+
+class WorkItemType(models.TextChoices):
+    TICKET_MISSING_INFO = "ticket_missing_info", "工单信息待补全"
+    TICKET_INTAKE_FAILED = "ticket_intake_failed", "智能受理待人工接管"
+    TICKET_CUSTOMER_REPLY = "ticket_customer_reply", "客户回复待确认"
+    TICKET_CLOSE = "ticket_close", "工单待人工关闭"
+    SUPPORT_ANALYSIS_FAILED = "support_analysis_failed", "支持分析待人工接管"
+    KNOWLEDGE_DISTILLATION_FAILED = (
+        "knowledge_distillation_failed",
+        "知识蒸馏待人工接管",
+    )
+    ASSET_REVIEW = "asset_review", "知识资产待审核"
+    TOOL_CONFIRMATION = "tool_confirmation", "高风险工具待确认"
+
+
+class WorkItem(models.Model):
+    public_id = models.UUIDField(default=uuid.uuid4, unique=True, editable=False)
+    task_type = models.CharField(max_length=64, choices=WorkItemType.choices)
+    status = models.CharField(
+        max_length=24,
+        choices=WorkItemStatus.choices,
+        default=WorkItemStatus.ACTIVE,
+    )
+    object_type = models.CharField(max_length=64)
+    object_id = models.CharField(max_length=80)
+    ticket = models.ForeignKey(
+        "tickets.Ticket",
+        null=True,
+        blank=True,
+        on_delete=models.CASCADE,
+        related_name="work_items",
+    )
+    title = models.CharField(max_length=200)
+    description = models.TextField(blank=True)
+    payload = models.JSONField(default=dict, blank=True)
+    assignee = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        null=True,
+        blank=True,
+        on_delete=models.SET_NULL,
+        related_name="assigned_work_items",
+    )
+    created_by = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        null=True,
+        blank=True,
+        on_delete=models.SET_NULL,
+        related_name="created_work_items",
+    )
+    completed_by = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        null=True,
+        blank=True,
+        on_delete=models.SET_NULL,
+        related_name="completed_work_items",
+    )
+    completed_at = models.DateTimeField(null=True, blank=True)
+    due_at = models.DateTimeField(null=True, blank=True, db_index=True)
+    created_at = models.DateTimeField(auto_now_add=True)
+    updated_at = models.DateTimeField(auto_now=True)
+
+    class Meta:
+        ordering = ["-created_at"]
+        constraints = [
+            models.UniqueConstraint(
+                fields=["task_type", "object_type", "object_id"],
+                condition=Q(status=WorkItemStatus.ACTIVE),
+                name="unique_active_work_item_target",
+            )
+        ]
+        indexes = [
+            models.Index(fields=["status", "task_type", "created_at"]),
+            models.Index(fields=["object_type", "object_id"]),
+            models.Index(fields=["assignee", "status", "created_at"]),
+        ]