perf(assets): 优化节点树

修改树策略，做读优化，写的速度降低

apps/perms/exceptions.py

@@ -0,0 +1,14 @@
+from rest_framework import status
+from django.utils.translation import gettext_lazy as _
+
+from common.exceptions import JMSException
+
+
+class AdminIsModifyingPerm(JMSException):
+    status_code = status.HTTP_409_CONFLICT
+    default_detail = _('The administrator is modifying permissions. Please wait')
+
+
+class CanNotRemoveAssetPermNow(JMSException):
+    status_code = status.HTTP_409_CONFLICT
+    default_detail = _('The authorization cannot be revoked for the time being')