Return a copy of this Implementation with any fields newer than the
negotiated protocol version stripped, so the wire output stays valid for
the peer's version. title applies from 2025-06-18 (BaseMetadata);
description, websiteUrl, and icons apply from 2025-11-25.
name/version are always present. This lets a server (or client) hold a
fully-populated identity while emitting only the fields its peer understands.
Return a copy of this Implementation with any fields newer than the negotiated protocol version stripped, so the wire output stays valid for the peer's version. title applies from 2025-06-18 (BaseMetadata); description, websiteUrl, and icons apply from 2025-11-25. name/version are always present. This lets a server (or client) hold a fully-populated identity while emitting only the fields its peer understands.