Make a show episode now (a preview or an extra).

Make one episode now. kind: "preview" (the default) is made from the show's sources like any episode and priced the same, held for the creator to hear and never published, and claims nothing; pass itemId to make it from one item, even one that already aired. kind: "extra", on a show made in Sleeper, goes out like any other and claims its item. A show an outside app makes takes previews only (409 show_made_outside). Two calls: without userConfirmed it quotes (nothing made); with userConfirmed: true it charges and queues. If the episode cannot be queued it is marked failed and nothing is charged (409 show_episode_not_queued; try again when the one queued finishes). Refused while the show cannot run (sources, caps), with 409 project_precondition_failed / cast_precondition_failed / show_not_ready while the project cannot make an episode, and with 409 show_cap_reached when the month cannot pay for one. Requires Idempotency-Key.