Re-pose an existing sprite into a new target pose while preserving the character, taking a source image (URL or base64), a pose name (or "Other" with a free-text description), and an optional n (1-4) for how many variations to produce. Only works with sprite image types (not icons, screenshots, etc.). The job result is an array of pose results, each containing the generated image url, the pose and description used, and a suggested motion_prompt tuned for that pose. Credits are held when the job is accepted and refunded if it fails or is cancelled; the charge scales with the number of images generated. This is typically the first step before animating: call generatePose to set the character's pose, then feed the result (and its suggested motion_prompt) into animateSprite for the best animation quality; use rotateSprite instead when you want to change the camera angle rather than the pose. Pass an optional request_id to tag the results so you can locate them later via listGenerations (type spritesheet). Requires an API key (user scope). The call returns 202 with a job id - poll getApiJob (pass wait 30 to long-poll) honouring poll_after_ms, until status is succeeded; its result field is exactly the response documented for this operation. Synchronous responses are deprecated but still supported: pass `async: false` to block until the result is ready and receive it as the response body. Synchronous calls run on the same queue: the response carries an X-Ludo-Job-Id header, and a job still running after 15 minutes comes back as 202 with the job instead of an error. Each account may have up to 50 generations queued or running at once via the API; a request beyond that returns 429 (code PENDING_JOBS_LIMIT).