Route Mapping

LegacyV4Notes
POST /v1/headless/runsPOST /v4/executeEphemeral one-liner mode.
session-like client statePOST /v4/sessions.startBackend-persisted defaults for policy/route/risk.
run invokePOST /v4/sessions/{sessionId}/executions.executeInherits session defaults when omitted.