💩(backend) pass room config and user role data to LiveKit token utility

Extend LiveKit token creation utility with additional room configuration
and user role parameters to properly adapt room_admin grants and
publish sources based on permission levels.

This creates technical debt in utility function design that should be
refactored into proper service architecture for token
generation operations in future iterations.

src/backend/core/api/serializers.py

@@ -136,6 +136,8 @@ class RoomSerializer(serializers.ModelSerializer):
             )
             output["accesses"] = access_serializer.data
 
+        configuration = output["configuration"]
+
         if not is_admin_or_owner:
             del output["configuration"]
 
@@ -152,7 +154,11 @@ class RoomSerializer(serializers.ModelSerializer):
             room_id = f"{instance.id!s}"
             username = request.query_params.get("username", None)
             output["livekit"] = utils.generate_livekit_config(
-                room_id=room_id, user=request.user, username=username
+                room_id=room_id,
+                user=request.user,
+                username=username,
+                configuration=configuration,
+                is_admin_or_owner=is_admin_or_owner,
             )
 
         output["is_administrable"] = is_admin_or_owner