feat: option to disallow public org registration (#6917)

* feat: return 404 or 409 if org reg disallowed

* fix: system limit permissions

* feat: add iam limits api

* feat: disallow public org registrations on default instance

* add integration test

* test: integration

* fix test

* docs: describe public org registrations

* avoid updating docs deps

* fix system limits integration test

* silence integration tests

* fix linting

* ignore strange linter complaints

* review

* improve reset properties naming

* redefine the api

* use restrictions aggregate

* test query

* simplify and test projection

* test commands

* fix unit tests

* move integration test

* support restrictions on default instance

* also test GetRestrictions

* self review

* lint

* abstract away resource owner

* fix tests

* lint

internal/repository/restrictions/events.go

@@ -0,0 +1,53 @@
+package restrictions
+
+import (
+	"github.com/muhlemmer/gu"
+
+	"github.com/zitadel/zitadel/internal/eventstore"
+)
+
+const (
+	eventTypePrefix = eventstore.EventType("restrictions.")
+	SetEventType    = eventTypePrefix + "set"
+)
+
+// SetEvent describes that restrictions are added or modified and contains only changed properties
+type SetEvent struct {
+	*eventstore.BaseEvent          `json:"-"`
+	DisallowPublicOrgRegistrations *bool `json:"disallowPublicOrgRegistrations,omitempty"`
+}
+
+func (e *SetEvent) Payload() any {
+	return e
+}
+
+func (e *SetEvent) UniqueConstraints() []*eventstore.UniqueConstraint {
+	return nil
+}
+
+func (e *SetEvent) SetBaseEvent(b *eventstore.BaseEvent) {
+	e.BaseEvent = b
+}
+
+func NewSetEvent(
+	base *eventstore.BaseEvent,
+	changes ...RestrictionsChange,
+) *SetEvent {
+	changedEvent := &SetEvent{
+		BaseEvent: base,
+	}
+	for _, change := range changes {
+		change(changedEvent)
+	}
+	return changedEvent
+}
+
+type RestrictionsChange func(*SetEvent)
+
+func ChangePublicOrgRegistrations(disallow bool) RestrictionsChange {
+	return func(e *SetEvent) {
+		e.DisallowPublicOrgRegistrations = gu.Ptr(disallow)
+	}
+}
+
+var SetEventMapper = eventstore.GenericEventMapper[SetEvent]