[Maps] Add Tracestack Topo to the maps selection

[dcjkfgdjhd]

Is your feature request related to a problem? Please describe

On openstreetmap.org they now (?) offer a new topo map which has a very similar design to the Freizeitkarte design.

It is called "Tracestack Topo", see https://www.openstreetmap.org/#layers=P

Describe the solution you'd like

It would be great if you could add this topo as a choice to GClh. Thank you very much!

Additional context

No response

[capoaira]

Unfortunately, the map is not 100% free: https://www.tracestrack.com/#pricing

[dcjkfgdjhd]

Would it work if each user needs to get their own personal free API key?

[2Abendsegler]

It would probably be useful to set up an API key for each user for the map layer. But the effort involved seems too great to me at the moment. There would also probably be a lot of requests from users to set up the API key. This effort also seems too great to me at the moment.

We'll leave the issue open for now for these both problems. Maybe someone will be found who has the time and desire to work on it.