Converts thin_dump XML (full mode: allocation map of one thin LV) and
thin_delta XML (delta mode: differences between two thin snapshots)
into the borg create --map format. The docstring documents the full
workflow including the reserve/release_metadata_snap steps and the
snapshot discipline needed for --reuse-from.
Also add a docs section pointing from the --read-special LVM example
to the input map based approach.
Co-Authored-By: Claude Fable 5 <[email protected]>
