Forward SIGTERM/SIGINT to in-flight jobs implementing the new
Illuminate\Contracts\Queue\Interruptible contract, and dispatch
Illuminate\Queue\Events\WorkerInterrupted on shutdown. Mirrors the
behaviour Illuminate\Queue\Worker introduced upstream (PRs #59833,
#59848), broadened to Torque's N concurrent fibers per worker so every
running command receives interrupted() before the worker exits. A
thrown handler from one job does not block the others.

Refactor the fiber loop to build the StreamJob up front so each slot's
job can be tracked in $slotJobs alongside $slotStarts. processMessage()
and handleFailure() now accept the prepared job; both stay private.

Also register Livewire's and Flux's service providers in tests/TestCase
so Feature tests booting TorqueServiceProvider no longer fail with
'Target class [livewire.finder] does not exist'.