More correct error if no addresses are found

mtglib/internal/telegram/init.go

 
 import (
 	"context"
+	"errors"
 
 	"github.com/9seconds/mtg/v2/essentials"
 )
 
+var ErrNoAddresses = errors.New("no addresses")
+
 type preferIP uint8
 
 const (

mtglib/internal/telegram/telegram.go

 		addresses = append(t.pool.getV6(dc), t.pool.getV4(dc)...)
 	}
 
-	var (
-		conn essentials.Conn
-		err  error
-	)
+	var conn essentials.Conn
+
+	err := ErrNoAddresses
 
 	for _, v := range addresses {
 		conn, err = t.dialer.DialContext(ctx, v.network, v.address)