Update or remove architecture diagram

[evankanderson]

The diagram here is woefully out of date: https://minder-docs.stacklok.dev/developer_guide/architecture

[evankanderson]

Some things that are missing:

• Keycloak (both as a dependency, and reacting to user-deleted events)
• OpenFGA (as a dependency, in the gRPC middleware path)
• gRPC triggers events on profile change
• telemetry logging

[evankanderson]

There's probably more, but that's a start.