a866ea8abd
计划阶段发现:PhoneCall.channel ∈ {phone_call,voice_call}(models.py docstring
自证 calls are not tied to a messaging channel),v2把通话四列放进
(day,channel,user)宽表在channel=all聚合时双计。拆出employee_call_daily
(day,user_id)独立小表;§1.2补#9,P3重排#10-#14,§3改6张表,§4链路更新