v0.3.1 — SHP_005 false-positive fix

Fixed

• SHP_005 (shape_dist_traveled decreasing) now evaluates values in shape_pt_sequence order instead of file-row order. GTFS does not require shapes.txt rows to be pre-sorted by sequence, so feeds that list shape points out of sequence order (valid) produced spurious CRITICAL errors — e.g. all 5,774 on the Athens feed (mdb-3220) were false positives (file order shows 5,774 decreases; sequence order shows 0, matching MobilityData's decreasing_shape_distance). The check moved to the stage that already sorts shape points by sequence; no other rule was affected. On Athens: overall 79.2 → 84.8, publish/spec 86.2 → 100.