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/router/admin.go

@@ -50,7 +50,7 @@ func Init(g *gin.Engine) {
 
 	RustdeskCmdBind(adg)
 	DeviceGroupBind(adg)
-	//访问静态文件
+	//access static files
 	//g.StaticFS("/upload", http.Dir(global.Config.Gin.ResourcesPath+"/upload"))
 }