New utility scans every catalog file under a directory
tree and reports the primary-key id range, gap count,
first gap, and recommended next id (smallest gap if any,
else max+1). Useful when adding new entries without
conflicts: instead of opening the file in --info to read
the current max id, run --catalog-id-range and pick the
recNext value.
Optional --magic <WXXX> filter narrows to one format
family. Output is sorted by file path for deterministic
shell-pipeline behavior.
Skips files whose format has no --info-* surface
(asset formats like .wom/.wob/.whm). Permission-denied
subdirs handled gracefully via skip_permission_denied.
Reuses the same primary-key heuristic + foreign-key
filter as --catalog-pluck and --catalog-find.
CLI flag count 1198 -> 1199.
