Moves the two manifest-drift fix handlers (--repair-zone,
--repair-project) out of main.cpp into a new cli_repair.{hpp,cpp}
module. Both auto-fix the common manifest-vs-disk
inconsistencies that accumulate when zones are hand-edited or
partially copied — adding orphan WHM tiles to the manifest,
syncing the hasCreatures flag with the actual creatures.json
content, and warning (not removing) for tiles in the manifest
without backing files. Both honor --dry-run for safe previews.
main.cpp shrinks by 155 lines (3,946 to 3,791).
