Archive/retire the @migtools/lib-ui package and repo

[mturley]

Nicole from PF reached out to ask about the lib-ui package and how it will impact efforts to upgrade apps using it to PF5/PF6/etc. We determined that lib-ui has outlived its usefulness now that Konveyor is focused on a single UI, and all of the non-tackle2-related usage is legacy code that either does not matter or could easily remove/replace lib-ui.

To close this issue we need to archive the repo and deprecate the package, evaluate the effort required to remove it from all projects currently using it and do so. In some cases it may be as simple as removing unused code, and in others we may need to temporarily copy-paste some of the lib-ui code into product repos. Note that a good chunk of the lib-ui exports are being moved to https://github.com/patternfly-labs/react-table-batteries as well.