Auth: creates a hook in the user mapping flow (#37190)

* wip

* Auth Info: refactored out into it's own service

* Auth: adds extension point where users are being mapped

* Update pkg/services/login/authinfoservice/service.go

Co-authored-by: Joan López de la Franca Beltran <joanjan14@gmail.com>

* Update pkg/services/login/authinfoservice/service.go

Co-authored-by: Joan López de la Franca Beltran <joanjan14@gmail.com>

* Auth: simplified code

* moved most authinfo stuff to its own package

* added back code

* linter

* simplified

Co-authored-by: Joan López de la Franca Beltran <joanjan14@gmail.com>

pkg/models/user.go

@@ -10,6 +10,7 @@ var (
 	ErrUserNotFound      = errors.New("user not found")
 	ErrUserAlreadyExists = errors.New("user already exists")
 	ErrLastGrafanaAdmin  = errors.New("cannot remove last grafana admin")
+	ErrProtectedUser     = errors.New("cannot adopt protected user")
 )
 
 type Password string

pkg/models/user_auth.go

@@ -98,8 +98,6 @@ type GetUserByAuthInfoQuery struct {
 	UserId     int64
 	Email      string
 	Login      string
-
-	Result *User
 }
 
 type GetExternalUserInfoByLoginQuery struct {