Adds structured ship provenance surface to eliminate delivery-path opacity:
New lane events:
- ship.prepared — intent to ship established
- ship.commits_selected — commit range locked
- ship.merged — merge completed with provenance
- ship.pushed_main — delivery to main confirmed
ShipProvenance struct carries:
- source_branch, base_commit
- commit_count, commit_range
- merge_method (direct_push/fast_forward/merge_commit/squash_merge/rebase_merge)
- actor, pr_number
Constructor methods added to LaneEvent for all four ship events.
Tests:
- Wire value serialization for ship events
- Round-trip deserialization
- Canonical event name coverage
Runtime: 465 tests pass
ROADMAP updated with IMPLEMENTED status
This closes the gap where 56 commits pushed to main had no structured
provenance trail — now emits first-class events for clawhip consumption.
8a8ca8a355