live-verify

Two-part gate for gflow-cli feature/fix work. Part 1 (Pre-flight): use when starting work on a gflow-cli feature or fix — confirms the checkout reflects current develop before investing effort. Part 2 (Live-verify): use before claiming gflow-cli work done, especially anything touching a generation code path (t2i/i2i/i2v/t2v/r2v) — requires live evidence against real Flow, not just offline tests.