feat(api): feature flags (#7356)

* feat(api): feature API proto definitions

* update proto based on discussion with @livio-a

* cleanup old feature flag stuff

* authz instance queries

* align defaults

* projection definitions

* define commands and event reducers

* implement system and instance setter APIs

* api getter implementation

* unit test repository package

* command unit tests

* unit test Get queries

* grpc converter unit tests

* migrate the V1 features

* migrate oidc to dynamic features

* projection unit test

* fix instance by host

* fix instance by id data type in sql

* fix linting errors

* add system projection test

* fix behavior inversion

* resolve proto file comments

* rename SystemDefaultLoginInstanceEventType to SystemLoginDefaultOrgEventType so it's consistent with the instance level event

* use write models and conditional set events

* system features integration tests

* instance features integration tests

* error on empty request

* documentation entry

* typo in feature.proto

* fix start unit tests

* solve linting error on key case switch

* remove system defaults after discussion with @eliobischof

* fix system feature projection

* resolve comments in defaults.yaml

---------

Co-authored-by: Livio Spring <livio.a@gmail.com>

internal/api/grpc/system/instance.go

@@ -151,7 +151,7 @@ func (s *Server) ListDomains(ctx context.Context, req *system_pb.ListDomainsRequ
 }
 
 func (s *Server) AddDomain(ctx context.Context, req *system_pb.AddDomainRequest) (*system_pb.AddDomainResponse, error) {
-	instance, err := s.query.Instance(ctx, true)
+	instance, err := s.query.InstanceByID(ctx)
 	if err != nil {
 		return nil, err
 	}