[Feature Request] Add support for jtx board

[nakibrayane]

I am migrating from a self hosted Radicale server that I used for years to etesync.

And the only thing holding me back is that I can't access my collections from jtx board.

jtx board (in my opinion) has the best compliance with the iCal standard, And it have the best UX.

I reported this issue to the jtx board developers (https://github.com/TechbeeAT/jtxBoard/issues/1576) and they said:

Hi @nakibrayan3 ! Thank you for your proposal. Basically jtx Board is open to any sync software to synchronize journals, notes and tasks, but it needs to be implemented on the side of the sync software. So there is a "contract" that defines how another app can communicate with jtx Board (and its database). I don't have the time and resources to work on something like that, but feel free to make such a request with etesync directly.

...

Regards, Patrick

I can't implement this feature myself, and I really need it, I would really appreciate it if it was implemented.

DAVx⁵ can sync with jtx board, hopefully this would help.

thank you.