Continuing the asmap integration of #16702 which added mapped_as
to the rpc getpeerinfo output, this adds the mapped AS to the Peers detail window in the GUI wallet.
$ src/qt/bitcoin-qt -asmap=<path-to-asmap-file>
(asmap on)
$ src/qt/bitcoin-qt
(asmap off)
Added a tooltip and a couple of minor fixups.