420 Registry architecture

The 420 Registry application reads canonical state from ProtocolRegistry and may use 420Indexer/Explorer/Search as convenience projections. Security-sensitive clients should recheck canonical chain state before acting.

Genesis service IDs are frozen through ServiceIds420; extension IDs require explicit governance approval and descriptor commitments. Registration profiles bind component type, manifest hash, dependency root and interface hash to the published implementation.

The frontend is replaceable. ProtocolRegistry is the canonical authority for this domain.