Phase 53c — Old Marrow made reachable on every route, a coverage-floor audit lands
What changed
Narrowed fishing-village column 1 to fv-2 alone, so the quest-giver (Old Marrow) sits on 100% of legal routes instead of being one of two column-1 options — matching what docs/story.md and the map file's own header comment already claimed. Homed three more S-02 NPCs (Captain Blackwater, the Coastal Beggar, the Fisherman's Daughter) into the post-boss column, one per lane. Added auditRouteCoverage and a coverage-floor test pinning fv-1/fv-2/fv-6 at 100%, plus a witness test that reaches Old Marrow through real navigation and activates starting-quest — the assertion that could not pass before this phase.
Why it changed
The quest-giver placement the docs already asserted was never actually true in the shipped graph — a second column-1 node let a route bypass Old Marrow entirely, so "start a quest" wasn't guaranteed reachable despite reading as guaranteed everywhere it was described.