feat(cli): live serial mirror for packet log

[benallfree]

Hey meshcore team, here is a log tailing addition for bench testing. I found it particularly helpful because it will stream log events out serial in realtime instead of the log dump.

I prefer this to a compiler flag because it can ship with any repeater and be used in the field.

Example:

log tail on
10:53:53 - 15/5/2024 U: RX, len=28 (type=PAYLOAD_TYPE_TXT_MSG (0x02), route=D, payload_len=20) SNR=8 RSSI=-6 score=1000 [08 -> 26]
10:53:53 - 15/5/2024 U: TX, len=26 (type=PAYLOAD_TYPE_TXT_MSG (0x02), route=D, payload_len=20) [08 -> 26]
10:53:54 - 15/5/2024 U: RX, len=24 (type=PAYLOAD_TYPE_TXT_MSG (0x02), route=D, payload_len=20) SNR=8 RSSI=-10 score=1000 [08 -> 26]
10:53:55 - 15/5/2024 U: RX, len=22 (type=PAYLOAD_TYPE_TXT_MSG (0x02), route=D, payload_len=20) SNR=8 RSSI=-19 score=1000 [08 -> 26]
10:53:55 - 15/5/2024 U: RX, len=12 (type=PAYLOAD_TYPE_ACK (0x03), route=D, payload_len=6) SNR=10 RSSI=-28 score=1000
10:53:56 - 15/5/2024 U: TX, len=10 (type=PAYLOAD_TYPE_ACK (0x03), route=D, payload_len=6)
10:53:56 - 15/5/2024 U: RX, len=8 (type=PAYLOAD_TYPE_ACK (0x03), route=D, payload_len=6) SNR=8 RSSI=-9 score=1000
10:54:04 - 15/5/2024 U: TX, len=12 (type=PAYLOAD_TYPE_OTA (0x0C), route=F, payload_len=10)
10:54:04 - 15/5/2024 U: RX, len=13 (type=PAYLOAD_TYPE_OTA (0x0C), route=F, payload_len=10) SNR=8 RSSI=-10 score=1000

[benallfree]

Added follow-up commit: packet log lines now print symbolic payload type names (e.g. type=PAYLOAD_TYPE_OTA (0x0C)) instead of bare decimal type=12.

• mesh::formatPayloadType() lookup table in Packet.cpp
• Used by repeater/room-server packet log (serial tail + on-device log file)