Development record

The session chapter says the blueprint refuses outside a checkout abcd manages and for a release that publishes no checksum for the linux/amd64 binary (.abcd/development/brief/04-surfaces/37-session.md:127-129). It also refuses a release older than a floor, naming firstSessionRelease (internal/core/session/blueprint.go:99, refusal at :466), and a checkout whose origin names no repository on github.com. The chapter states neither. The floor is itself stale: its comment says the cut that first ships the verb sets it, yet it reads v0.17.0 while the changelog's 0.16.0 section (CHANGELOG.md:85) already describes the session page, so the refusal can direct a person to a release that does not exist.