feat: multiple domains (#188)

* check uniqueness on create and register user

* change user email, reserve release unique email

* usergrant unique aggregate

* usergrant uniqueness

* validate UserGrant

* fix tests

* domain is set on username in all orgs

* domain in admin

* org domain sql

* zitadel domain org name

* org domains

* org iam policy

* default org iam policy

* SETUP

* load login names

* login by login name

* login name

* fix: merge master

* fix: merge master

* Update internal/user/repository/eventsourcing/user.go

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

* fix: fix unique domains

* fix: rename env variable

Co-authored-by: adlerhurst <silvan.reusser@gmail.com>
Co-authored-by: Livio Amstutz <livio.a@gmail.com>

internal/user/model/user_view.go

@@ -18,6 +18,7 @@ type UserView struct {
 	PasswordChanged        time.Time
 	LastLogin              time.Time
 	UserName               string
+	LoginNames             []string
 	FirstName              string
 	LastName               string
 	NickName               string
@@ -61,12 +62,13 @@ const (
 	USERSEARCHKEY_EMAIL
 	USERSEARCHKEY_STATE
 	USERSEARCHKEY_RESOURCEOWNER
+	USERSEARCHKEY_LOGIN_NAMES
 )
 
 type UserSearchQuery struct {
 	Key    UserSearchKey
 	Method model.SearchMethod
-	Value  string
+	Value  interface{}
 }
 
 type UserSearchResponse struct {