Feature Request: Inav Telemetry to Meshtastic over UART/Serial.

[rotorHead82]

Current Behavior

Inav currently can talk to certain SIM/sms modules to send telemetry and recieve commands through SMS messages.
Having the same functinality by using a Mesthastic node instead would be great. It provides a great backup link for tracking and added security to be able to activate RTH for example should your TX loose connection.
I already use a Meshtastic node with a GNSS module as a backup tracker through my own Meshtastic network in the area I fly. In case of a crash the node will provide easy location of the wreck as it is a standalone unit that run on its own battery and has its own gnss module. When airborne the range for a Meshtastic node is easily 100s of km if line of sight. (300km personal best from a com. Airplane.)
The programming for this should be fairly easy as all that needs to be sendt from the FC to the Node is a simple string with the telemetry data. (Ie: The text message the SMS/Sim module sends) The Meshtastic node can be configured to pass this through to the Meshtastic network as a message and oposite for recieved messages.

Desired Behavior

Having Inav send a string at configurable interval with Telemetry data through a UART connected to a Mesthastic Node.
Secondary, Have Inav react to receved messages/strings coming from the Mesthastic node activating functions. Examples: RTH, RTH_Land, Change altitude etc.

Suggested Solution

Modify the already existent SIM/SMS function to only send a simple string of telemetry data. No AT commands or module control needed. The Meshtastic node will take this sting and spit it out as a message to the network.
Having the option for a "codeword" needed in a recieved message for Inav to react to it provides tamper proofing should the Meshtasic node not be set up for a private connection.

Who does this impact? Who is this for?

Anyone using Mesthastic nodes or have a Mesthastic Network where they fly. Anyone who wants a backup tracking and control system. The transmitted packages will be retransmitted through anyones nodes so a private network is not needed for good coverage. If the Meshtastic node have its own GPS and battery it will also act as a standalone tracker and send positiondata even after a crash or the FC is disabled.

Additional context

https://meshtastic.org/
https://meshtastic.org/docs/configuration/module/serial/
Meshtastic serial Module config alternative: -TEXTMSG- will allow you to send a string over the serial port to the meshtasticdevice, which will be broadcasted as a text message to the default channel. Any text message received from the mesh will be sent to the serial port as follows: : .