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>

model/model.go

@@ -7,8 +7,8 @@ import (
 type StatusCode int
 
 const (
-	COMMON_STATUS_ENABLE   StatusCode = 1 //通用状态 启用
-	COMMON_STATUS_DISABLED StatusCode = 2 //通用状态 禁用
+	COMMON_STATUS_ENABLE   StatusCode = 1 // common status: enabled
+	COMMON_STATUS_DISABLED StatusCode = 2 // common status: disabled
 )
 
 type IdModel struct {