Staging demo. Upload an image; the cutout is composited on a saturated background so edge decontamination (I4) is visible. The transparent checkerboard shows the true alpha.
{base}/v1/remove with Authorization: Bearer {key} and a
multipart image file. The response url is a short-TTL presigned R2 link.
Note: a browser call needs CORS on the gateway (see DEPLOY-STAGING.md) — or serve this page
same-origin as the API.