Extend a sequence

What it does

extend_sequence plans and generates additional shots that continue an existing arc, inheriting the same locked continuity references so the new shots match the old ones.

curl -X POST https://cadenza.media/api/v1/extend_sequence \
  -H "Authorization: Bearer cadk_..." -H "Content-Type: application/json" \
  -d '{
    "original_intent": "15 second trail shoe launch film",
    "extension": "add two shots showing the post-run recovery ritual"
  }'

Statelessness note

During the beta the call is stateless: you pass the originating intent, and determinism plus the shared locked references keep the result consistent. A stored-sequence handle is planned and tracked on the build board.