v1.2.0 — no supported write path accepts a retired department (AID-1085)

Department::scopeActive() shipped with v1.0 and had zero callers. TicketService
::createTicket() and both FormRequests ignored it, so every write path the
package owns — its own REST API included — accepted a department the operator
had taken out of service, and the update rule allowed MOVING a ticket into one.

A minor with a reversible compatibility path, not a breaking release: it
corrects an invariant the package always implied. The SemVer risk of changing a
default is real; laratickets.departments.enforce_active=false restores the
pre-1.2.0 behaviour on every path at once. The default is read at the point of
use, so a consumer with a published config still gets the safe value.

Update is narrower than create: a ticket already sitting in a retired
department stays editable. Direct Eloquent writes remain outside the contract.

Consumer conformance gate against the identical tree: clientes 1794 passed /
1 skipped / 0 failed, matching baseline, and green UNDER enforcement.