One build node on another version stopped every build of the language. The agreed toolchain is now the strict majority's; a tie still waits and names the versions.
Claude-Session: https://claude.ai/code/session_01NcbgfJ9Gum47zkFKWRaovL
The indexer needs a module's manifest, lock hashes and toolchain to compute its new-form fingerprint, and has none of them (ADR 0465 clauses 1, 2, 5): the forge messages now carry the first two, a module keeps its inputs so it can be computed again when a toolchain is reported, and the build modules' toolchain keys have a layout and an agreement rule.