 role_id int(11) auto_increment  not_null
 agent_id varchar(100)  not_null
 role varchar(50)  not_null
 status enum('active','suspended','disabled')  default (active)
 suspension_reason text  default null
 suspended_at timestamp NULL  default null
 created_at timestamp NULL  default(current_timestamp)
 updated_at timestamp NULL  default(current_timestamp) ON UPDATE current_timestamp()

--
primary role_id
unique agent_id agent_id
idx_agent_id agent_id 
idx_role role 
idx_status status
  
##
engine innodb
character_set utf8mb4
collate utf8mb4_unicode_ci