Preview registering a jurisdiction

Report what a DIRECT_REQUEST POST /registrations for a jurisdiction would do, without creating anything. Send an Organization-Id, Connection-Id or Entity-Id header to say which organization it is for

result is OK when a new registration would be opened, ABSORBED when an existing sales-tax registration would cover the jurisdiction instead (returned as registration), PLAN_UPGRADE_REQUIRED when the organization's plan does not include the registration, or SALES_TAX_REGISTRATION_REQUIRED when a retail delivery fee registration needs an active sales-tax registration in the jurisdiction first

It assumes the jurisdiction has a nexus, like the register dialog, which only previews jurisdictions the organization is exposed in. A jurisdiction with no nexus reports OK

This is read-only: it stores nothing and never creates a registration.