Quickstart

POST   /sessions                      → session_id
POST   /sessions/:id/trigger          → set trigger
POST   /sessions/:id/nodes            → add nodes
POST   /sessions/:id/edges            → connect nodes
POST   /sessions/:id/forms            → create form drafts
PATCH  /sessions/:id/nodes/:node_id   → wire form_id into nodes
POST   /sessions/:id/portals          → create portal drafts
POST   /sessions/:id/validate         → validate. Fix errors. Repeat.
POST   /sessions/:id/activate         → commit to production