Add three hard-stop checks to /gsd-next that prevent blind advancement:
1. Unresolved .continue-here.md checkpoint from a previous session
2. Error/failed state in STATE.md
3. Unresolved FAIL items in VERIFICATION.md
Also add a consecutive-call budget guard that prompts after 6
consecutive /gsd-next calls, preventing runaway automation loops.
All gates are bypassed with --force (prints a one-line warning).
Gates run in order and exit on the first hit to give clear,
actionable diagnostics.
Closes#1732
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
3a277f8ba8