Members improvements

[Gerrit91]

Description

While working on the CLI apply commands, I realized the following shortcomings in the API:

• Projects and tenants cannot be created with fixed IDs even for admins, this was possible with V1
  • For some reason we have an admin tenant create service method, but it does exactly the same as the one for the user
• ProjectServiceRemoveMemberResponse returns ProjectRole instead of ProjectMember, which is wrong
• Members do not contain their parent's ID (tenant member does not contain the tenant ID it belongs to, project member does not contain the project ID it belongs to)
  • This prevents a member apply because the member add requests require the parent IDs
  • I added a cli API to workaround this issue, we need to discuss how we want to solve it, just creating a wrapper struct in CLI does not work because it needs to be a proto.Message for marshaling

Used AI-Tools ✨

• None used for generation