Cleanup pass on the design doc per Ship's Msg 3 review. Two changes, no architecture shifts:
1. Merge commit message updated to locked verbose form:
"Merge external GitHub PR #{N}: {branch_slug}"
N derived from gh-pr-{N}/ regex; branch_slug = post-prefix portion. Embeds
the GitHub PR number explicitly so `git log --merges --grep "#90"` surfaces
the merge from PR number alone. Drops the v2 "{branch}"-only form.
2. "Open questions for Ship" section collapsed to "Locked decisions" —
the three Phase 2 items (backout flag, rebase-after-fix scope, merge commit
message format) were locked in Ship's reply on Msg 2 but the v2 doc still
framed them as open. Now restated as decisions so Ganymede doesn't re-debate
resolved items at line-level review.
Diffs reviewable against v2 (commit fa6cceb).
m3taversal
537cfd5ed7