cmotion api

POST /v1/render          { source, params? }  →  202 { job_id }
POST /v1/frame           { source, params? }  →  202 { job_id }
POST /v1/gif             { source, params? }  →  202 { job_id }
POST /v1/mesh            { source: <svg>, params? } → 202 { job_id }  (.glb)
POST /v1/vectorize       { source:<img path>, assets, params? } → 202 (.svg, centreline)
GET  /v1/jobs/<id>                              →  status + url when ready
GET  /v1/outputs/<file>                          →  streams the render
GET  /openapi.json                               →  OpenAPI 3.1 schema
GET  /test                                       →  synchronous smoke test
GET  /healthz                                    →  liveness