mpbb-list-subports returns lowercased port names, but mpbb-gather-archives requires correctly-cased port names

[ryandesign (Ryan Carsten Schmidt)]

mpbb-list-subports ​was recently changed to return lowercased port names, instead of correctly-cased port names. This was done intentionally, to deduplicate the list, in case a port name was specified with the wrong case somewhere, such as in a dependency. But it was two negative consequences:

1. The port names are displayed in various places on the buildbot web interface, and are now displayed with all-lowercased names instead of the correct case.
2. mpbb-gather-archives no longer gathers archives of ports whose names contain uppercase characters, because the list of archives to gather is constructed by running port -q location installed and \( $(cat "${option_work_dir}/all_ports") \)), and all_ports contains the lowercased names of all ports, and Boolean logic like this is currently handled case-sensitively by MacPorts base; see #56100.

Even if the case-sensitive handling of Boolean logic is fixed in MacPorts base, I would prefer for mpbb-list-subports to return port names in the canonical case, not lowercased, for aesthetic reasons.

[jmroot (Joshua Root)]

In 387064c27c616757509ec8462b72cfe512b228ad/mpbb:

Output canonical-case port names

Fixes: #56101