- types.ts: the D-01 backend-ladder seam (fixture -> wasm-router -> valhalla), D-03 null contract documented on the interface, D-07 day-one fields (RouteStep typed + RouteGeometry.cumulativeDistanceM, GUID-05/06 obligation) - route-fixtures.json: committed EMPTY seed with the ODbL header (license/attribution/notice, T-05-06) — plan 05-02 populates it