Set the business-hours schedule for a number

Create or REPLACE the open-hours / after-hours rule pair.

A PUT because it is a replace: calling it twice leaves two rules, not four. It writes into the same rule list /voice/inbound-routing/rules manages, so a hand-made rule at a lower priority still wins over it.

timezone is an IANA name and voice rejects anything it cannot load, so a schedule cannot silently run in UTC.