cleanup client/selector/lookup (#1937)

* cleanup client/selector/lookup

* add mdns router, remove registry from client

* fix roundtripper

* remove comment

* fix compile issue

* fix mucp test

* fix api router

selector/selector.go

@@ -3,35 +3,24 @@ package selector
 
 import (
 	"errors"
-
-	"github.com/micro/go-micro/v3/router"
 )
 
 var (
-	// DefaultSelector is the default selector
-	DefaultSelector = NewSelector()
-
 	// ErrNoneAvailable is returned by select when no routes were provided to select from
 	ErrNoneAvailable = errors.New("none available")
 )
 
 // Selector selects a route from a pool
 type Selector interface {
-	// Init a selector with options
-	Init(...Option) error
-	// Options the selector is using
-	Options() Options
 	// Select a route from the pool using the strategy
-	Select([]router.Route, ...SelectOption) (*router.Route, error)
+	Select([]string, ...SelectOption) (Next, error)
 	// Record the error returned from a route to inform future selection
-	Record(router.Route, error) error
-	// Close the selector
-	Close() error
+	Record(string, error) error
+	// Reset the selector
+	Reset() error
 	// String returns the name of the selector
 	String() string
 }
 
-// NewSelector creates new selector and returns it
-func NewSelector(opts ...Option) Selector {
-	return newSelector(opts...)
-}
+// Next returns the next node
+type Next func() string