Open Orbit briefing skill — selected by the Orbit pipeline when
Linear is the user's only connected connector, or when the user
explicitly scopes their daily digest to Linear. Pulls the past 24
hours of issue movement, status changes, assignments, and cycle
progress from the user's authenticated Linear connection and renders
the digest in Linear's native Inbox + cycle-progress visual language.
This skill should not be triggered manually — it is invoked by
Orbit's daily-digest scheduler against live Linear data.
