Clarify that the MULTIPART ACK chain terminates with a plain
PAYLOAD_TYPE_ACK (not a MULTIPART with remaining=0). For K extra
copies, the wire sequence is:
MULTIPART(remaining=K), MULTIPART(remaining=K-1), ...,
MULTIPART(remaining=1), then PAYLOAD_TYPE_ACK (plain).
All copies share the same ack_crc. Receivers MUST dedup at the
application layer by ack_crc, since each packet's hash differs.
Validated against upstream meshcore-dev/MeshCore @ 1a7b361
(Mesh::routeDirectRecvAcks, src/Mesh.cpp:362 — while-loop emits
MULTIPART(remaining=extra...1), then createAck(crc) plain ACK).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
swaitsandClaude Opus 4.7
3a8918fb0e