v0.7.0

• Handoffs now reconcile transcript records and linked task ledgers with an
  offline checker. The receipt records source counts and gaps, item outcomes,
  owned and dependency pull requests, and commits without pull requests.
• The checker reports complete, partial or invalid mechanical coverage.
  It cannot find promises hidden in records classified as context, discover
  unreported sources, or decide whether an outcome is supported semantically.
  An unfinished receipt never delays a low-quota stop.