pioneers: 0.12.3 -> 15.4

Semi-automatic update. These checks were performed:

- built on NixOS
- ran `/nix/store/524fd6bk2g3158rgmsc460p1ml0cqzlm-pioneers-15.4/bin/pioneersai -h` got 0 exit code
- ran `/nix/store/524fd6bk2g3158rgmsc460p1ml0cqzlm-pioneers-15.4/bin/pioneersai --help` got 0 exit code
- ran `/nix/store/524fd6bk2g3158rgmsc460p1ml0cqzlm-pioneers-15.4/bin/pioneersai help` got 0 exit code
- ran `/nix/store/524fd6bk2g3158rgmsc460p1ml0cqzlm-pioneers-15.4/bin/pioneersai --version` and found version 15.4
- ran `/nix/store/524fd6bk2g3158rgmsc460p1ml0cqzlm-pioneers-15.4/bin/pioneers-server-console -h` got 0 exit code
- ran `/nix/store/524fd6bk2g3158rgmsc460p1ml0cqzlm-pioneers-15.4/bin/pioneers-server-console --help` got 0 exit code
- ran `/nix/store/524fd6bk2g3158rgmsc460p1ml0cqzlm-pioneers-15.4/bin/pioneers-server-console --version` and found version 15.4
- ran `/nix/store/524fd6bk2g3158rgmsc460p1ml0cqzlm-pioneers-15.4/bin/pioneers-metaserver -h` got 0 exit code
- ran `/nix/store/524fd6bk2g3158rgmsc460p1ml0cqzlm-pioneers-15.4/bin/pioneers-metaserver --help` got 0 exit code
- ran `/nix/store/524fd6bk2g3158rgmsc460p1ml0cqzlm-pioneers-15.4/bin/pioneers-metaserver --version` and found version 15.4
- found 15.4 with grep in /nix/store/524fd6bk2g3158rgmsc460p1ml0cqzlm-pioneers-15.4
- found 15.4 in filename of file in /nix/store/524fd6bk2g3158rgmsc460p1ml0cqzlm-pioneers-15.4

cc "@viric"