feat: add intelligent support workflow

backend/apps/workitems/schemas.py

@@ -0,0 +1,31 @@
+from datetime import datetime
+
+from ninja import Schema
+
+
+class WorkItemOut(Schema):
+    public_id: str
+    task_type: str
+    status: str
+    object_type: str
+    object_id: str
+    ticket_id: int | None
+    ticket_no: str | None
+    title: str
+    description: str
+    payload: dict
+    assignee_id: int | None
+    created_at: datetime
+    updated_at: datetime
+    completed_at: datetime | None
+    due_at: datetime | None
+    sla_status: str
+
+
+class WorkItemMetricsOut(Schema):
+    active_count: int
+    overdue_count: int
+    due_soon_count: int
+    completed_within_sla_count: int
+    completed_overdue_count: int
+    by_task_type: dict[str, int]