Dynamically read and interpret the layer tree during app start

[ThomasEverding]

Issue description

Feature request:
In the 'Denkmalschutz'-project at IT.NRW, the available layers are not known beforehand. They depend on specific rights of the current user. Therefore, the layer tree must be read and interpreted from the (filtered) service capabilities.

Validations

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[ThomasEverding]

Thomas contacts IT.NRW for further details:

• which layer types / services need to be supported?
• is a project specific solution sufficient?
• Option 1: the layer configuration could be improved to check the access rights and remove unavailable services / layers
  • could be a good project specific solution, if the user details are available, these could be used to remove unavailable services without additional test requests
• Option 2: the health check feature could be improved to distinguish between network and authorization problems
• Option 3: the layer tree is fully dynamic, only the URL and service type are pre-configured. The layer tree will request nad parse the capabilities of all services
  • This is a lot of work

If a generic solution is implemented, a possible contribution to open pioneer trails should be discussed.