Go 1.26.4 and 1.25.11 ship with three stdlib security fixes

Go 1.26.4 and 1.25.11 are out, carrying three security fixes in the standard library, so updating takes priority over everything else in today's queue. On the proposal track, there's a thoughtful one to strip POST bodies and custom credential headers on cross-origin 307/308 redirects in net/http, which feels overdue, alongside an ARM64 SVE intrinsics proposal under GOEXPERIMENT for the SIMD-curious. And on the lighter side, someone has built a terminal clone of Settlers of Catan in Go, which is a reasonable use of an afternoon.