GO build failure for no apparent reason

https://github.com/compiler-explorer/compiler-workflows/actions/runs/18209302811/job/51846594278

```
+ ./make.bash
Building Go cmd/dist using /root/bootstrap/go. (go1.22.6 linux/amd64)
found packages main (build.go) and building_Go_requires_Go_1_24_6_or_later (notgo124.go) in /root/master/go/src/cmd/dist
Error: Process completed with exit code 1.
```

Start with the linked GitHub Actions job and reproduce the failure around ./make.bash. Read the log showing bootstrap Go 1.22.6 and the requirement for Go 1.24.6, then trace the workflow or infrastructure configuration that selects the Go version. Done means the affected build completes successfully with a documented cause.

Written by the indexing model from the issue text.