Nested
data class NestedMessageWithLengthField(val codecName: String, val lengthKind: LengthKind) : FieldReadStrategy
Nested @ProtocolMessage field bounded by a length annotation. Decoding slices the buffer to the length before invoking the nested codec, so a variable-size payload can be wrapped inside a framed region that also carries trailing fields (e.g., checksum) in a separate