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/eventstore/handler/v2/statement.go

@@ -532,6 +532,12 @@ func NewIsNullCond(column string) Condition {
 	}
 }
 
+func NewIsNotNullCond(column string) Condition {
+	return func(string) (string, []any) {
+		return column + " IS NOT NULL", nil
+	}
+}
+
 // NewTextArrayContainsCond returns a Condition that checks if the column that stores an array of text contains the given value
 func NewTextArrayContainsCond(column string, value string) Condition {
 	return func(param string) (string, []any) {