embeddedMCPMetadata only feeds interface validation now; its summary was
projected onto every schema payload as a constant-empty blob. Remove the
SchemaRegistry field, all three payload projections, the snapshot wire
field, the overview copy, the compact strip entry, and the jq policy gate.
Also delete the redundant io.Discard dead-code suppressor in
event_command.go (io has five genuine uses there).
Runtime assemble was stamping Snapshot.SourceHash with the registry
surface hash, so schema --all catalog_hash diverged from the CI dump
content source_hash and failed Policy. Also remap ContractFinal
Interface.Ref onto pinned MCP metadata so interface_type stays aligned.
Co-authored-by: Cursor <cursoragent@cursor.com>
玉澜