lang/go125: Add port
Introduction to Go 1.25ΒΆ
The latest Go release, version 1.25, arrives in August 2025, six months
after Go 1.24. Most of its changes are in the implementation of the
toolchain, runtime, and libraries. As always, the release maintains the
Go 1 promise of compatibility. We expect almost all Go programs to
continue to compile and run as before.