max Wire Size
The maximum number of bytes this codec ever writes for a single encoded value. Used by the @FramedBy slicing-scheme emitter to size the slack region at the front of the encode buffer so the prefix can be right-flushed against the body without shifting body bytes. For variable-width codecs (e.g. MQTT remaining-length: 1..4 bytes), this is the upper bound; for fixed-width codecs it equals the wire width. Implementations should pick the smallest value that satisfies wireSize(maxValueOnWire).asExact == maxWireSize.