Add: export the Gateway/internal. methods

[ev11ccaatt]

export the methods to avoid proto.GetExtension can't get any thing from rpc server,export the methods means i can add the methods in gateway/main.go like
`package main

import (
"flag"
"github.com/zeromicro/go-zero/core/conf"
"github.com/zeromicro/go-zero/gateway"
"gopkg.in/yaml.v2"
"log"
"os"
"strings"
)

var file = "etc/route.yaml"
var configFile = flag.String("f", "etc/versionApi.yaml", "config file")

type RouteMapping struct {
Method string yaml:"Method"
Path string yaml:"Path"
RpcPath string yaml:"RpcPath"
}

type Mappings struct {
Mappings []RouteMapping yaml:"Mappings"
}

func main() {
flag.Parse()
var c gateway.GatewayConf
conf.MustLoad(*configFile, &c)
addMapping()
gw := gateway.MustNewServer(c)
defer gw.Stop()
gw.Start()
}

func addMapping() {
data, err := os.ReadFile(file)
if err != nil {
log.Fatalf("无法读取 YAML 文件：%v", err)
}
var config Mappings
err = yaml.Unmarshal(data, &config)
if err != nil {
log.Fatalf("无法解析 YAML 数据：%v", err)
}
for _, mapping := range config.Mappings {
gateway.Methods = append(gateway.Methods, gateway.MethodConver(gateway.Method{
HttpMethod: mapping.Method,
HttpPath: adjustHttpPath(mapping.Path),
RpcPath: mapping.RpcPath,
}))
}
}

func adjustHttpPath(path string) string {
path = strings.ReplaceAll(path, "{", ":")
path = strings.ReplaceAll(path, "}", "")
return path
}
`