Retires REACT_APP_URL/URL2/URL3 in favor of REACT_APP_DOORMILE_URL across
every page (orders, deliveries, riders, tenants, pricing, profile, reports,
dispatch). Fixes several field-mapping and envelope-check bugs found along
the way, most notably that /admin/milers/:id routes (block, assign-vehicle,
edit, notify) key off milerprofileid, not userid, and that a miler's real
fields are phone/availabilitystatus/displayname, not contactno/status/
firstname+lastname (confirmed against a live read-only session).
Also fixes several silent-failure bugs uncovered during that audit: order
creation and order cancellation showed a success toast but gave no feedback
at all on failure (createorder1.js had a dead notifyadmin() call that left
the loading spinner stuck forever on every failed submit), and Tenants.js's
pricing/profile updates never surfaced a failed response to the operator.
The AI dispatch optimiser (routes.workolik.com/routemate.workolik.com) and
its jupiter.nearle.app delivery-commit call remain untouched by design —
separate solver service with no equivalent in the new API.
