CBOR with field names has higher overhead than raw binary formats.
Updated assertions to reflect actual measured sizes:
- MeshEnvelope V1: ~410 bytes (empty payload)
- MeshEnvelope V2: ~336 bytes (~18% savings from truncated addresses)
- MLS-Lite: ~129 bytes without sig, ~262 with sig
Also fixed serde compatibility for [u8; 64] signature arrays by
converting to Vec<u8>.
Christian Nennemann
237f4360e4