Go programs hit by Linux MPTCP use-after-free CVE-2026-98432

The golang-announce thread on CVE-2026-98432 is the one to open first: Go programs enable MPTCP by default on Linux, which pulls them into the kernel's TCP use-after-free bug whether the author asked for it or not. Alongside that, there's a proposal to spin out a unicode/ascii package of common ASCII helpers, and another to publish the analyzers currently buried inside gopls so the rest of the tooling ecosystem can actually use them.