backend: remove all `GET .../filtered...` endpoints and replace with `GET .../`

[dominiquegarmier]

for this we need to add the following to the base GET endpoints:

• sort by query params
• querying by metadata

[dominiquegarmier]

I will likely not have time to finish this issue. The idea is to replace all the different /resource/filtered... endpoints by the single endpoint /resouce which would allow to filter in many different ways.

Once we replace these endpoints in the frontend we will likely discover ways in which we want to filter which are not yet supported by the /resouce endpoints. We would then need to add these filter methods to that endpoint.

[wp99cp]

resolved with #2289