i18n: Translate all Chinese to English across the codebase

Translate Chinese comments, log/error messages, validator labels and
Swagger annotations to English throughout the source code, generated
Swagger docs, config files and CI workflows.

Make the English README primary: README.md now holds the English docs
and README_EN.md holds the Chinese version, with cross-language links
updated accordingly.

Note: the generated docs/ swagger files were translated in place; run
`go generate ./...` (swag init) to regenerate them from the now-English
annotations when a Go toolchain is available.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

http/controller/admin/login.go

@@ -17,13 +17,13 @@ import (
 type Login struct {
 }
 
-// Login 登录
-// @Tags 登录
-// @Summary 登录
-// @Description 登录
+// Login login
+// @Tags login
+// @Summary login
+// @Description login
 // @Accept  json
 // @Produce  json
-// @Param body body admin.Login true "登录信息"
+// @Param body body admin.Login true "login info"
 // @Success 200 {object} response.Response{data=adResp.LoginPayload}
 // @Failure 500 {object} response.Response
 // @Router /admin/login [post]
@@ -34,7 +34,7 @@ func (ct *Login) Login(c *gin.Context) {
 		return
 	}
 
-	// 检查登录限制
+	// check login limit
 	loginLimiter := global.LoginLimiter
 	clientIp := c.ClientIP()
 	_, needCaptcha := loginLimiter.CheckSecurityStatus(clientIp)
@@ -56,7 +56,7 @@ func (ct *Login) Login(c *gin.Context) {
 		return
 	}
 
-	// 检查是否需要验证码
+	// check whether a captcha is required
 	if needCaptcha {
 		if f.CaptchaId == "" || f.Captcha == "" || !loginLimiter.VerifyCaptcha(f.CaptchaId, f.Captcha) {
 			response.Fail(c, 101, response.TranslateMsg(c, "CaptchaError"))
@@ -95,7 +95,7 @@ func (ct *Login) Login(c *gin.Context) {
 		Platform: f.Platform,
 	})
 
-	// 登录成功，清除登录限制
+	// login successful, clear the login limit
 	loginLimiter.RemoveAttempts(clientIp)
 	responseLoginSuccess(c, u, ut.Token)
 }
@@ -129,10 +129,10 @@ func (ct *Login) Captcha(c *gin.Context) {
 	})
 }
 
-// Logout 登出
-// @Tags 登录
-// @Summary 登出
-// @Description 登出
+// Logout logout
+// @Tags login
+// @Summary logout
+// @Description logout
 // @Accept  json
 // @Produce  json
 // @Success 200 {object} response.Response
@@ -148,9 +148,9 @@ func (ct *Login) Logout(c *gin.Context) {
 }
 
 // LoginOptions
-// @Tags 登录
-// @Summary 登录选项
-// @Description 登录选项
+// @Tags login
+// @Summary login options
+// @Description login options
 // @Accept  json
 // @Produce  json
 // @Success 200 {object} []string