Add RINEX output, and fix some issues

[EmmanuelMess]

• Fixed a crash when no files to share available
• Added RINEX observations file
• Added RINEX navigations file and parsing

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[EmmanuelMess]

I have phantom observations that are marked as year 2048 for some reason, and only come from NAVSTAR. And I cannot seem to be able to receive ephemeris to test the RINEX yet.

[EmmanuelMess]

Okay, I will add a check to see when the fix is obtained, because clocks before that appear broken. @barbeau please run the CI to see if the tests pass.

[barbeau]

@EmmanuelMess While I appreciate your work on this, I have to say that I'm a bit hesitant to accept this contribution, primarily because I've spent a lot of time maintaining the RINEX file format for GnssLogger, and it's not trivial. I really don't have the bandwidth to take on maintaining another implementation of a RINEX file writer.

Maybe you could split off this contribution into a separate project to convert from the txt format to RINEX? I know there are a few such projects that exist, but I don't have any idea of how well they perform.

[EmmanuelMess]

@barbeau Any recommendations on under what framework the tool should be built? I fear there will be issues to run it.

The emulator execution in CI should be taken out and made a separate PR then.

[barbeau]

Any recommendations on under what framework the tool should be built?

I think most of the code in the PR is in kotlin? If so it should be pretty easy to convert this into a Java/Kotlin command line tool. If you don't want to host it in a separate GitHub repository, we could put it under a different module in this project - I would be ok with that. In particular, I'm not sure if there is a navigation message txt to RINEX conversion tool out there - IIRC most of the tools I've seen are for observations.

The emulator execution in CI should be taken out and made a separate PR then

Yes, that would be great if you could split that out.