Implement large MTU fragmentation on LoRa modulation

[sevenbitbyte]

LoRa modulation can't do larger than 255 byte packets. But our CLI can handle larger packets.

We could add a fragmentation layer when in LoRa modulation enabling normal sized ethernet frames.

Breaking a normal sized ethernet packet into multiple LoRa packets, which all go through the dispatcher normally. Fragements also allows the LoRa node to share the spectrum better as the dispatcher will delay transmissions to avoid cross talk. Meanwhile this removes the need for multiple ethernet layer ACK round trip times.

[mepholic]

we should carefully consider whether or not this is a good option. RNode gives an MTU of ~500 through a similar approach, but I feel like this violates some layering principals.

[mepholic]

this is probably not possible with LoRA from what I've read, but might still be possible with FSK mode. allegedly this is a "test mode" and possibly wasn't intended to be used in production when added by the manufacturer