Newest published aether. 0.643 fixes a heap-string-tracker codegen bug that
silently corrupted structs sharing a punned field prefix (no diagnostic) — a
real memory-safety fix, though not one aeb newly requires; the floor moves with
FETCH per the no-back-compat DSL policy. Verified against the real 0.643.0 linux
tarball: aeb builds clean, full suite 134/134; glibc floor GLIBC_2.34
(Debian-12 safe); all platform assets published.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TgmxVg44D6P5irWxhQkSAb