chore: 注入构建时版本信息到 /health 端点

现状:controller/tts.go:232 硬编码 Version: "2.0.0 (v3 API)",
不会随代码变化而更新,/health 无法反映实际跑的代码。
修复:四文件改动,实现构建时 ldflags 注入。
  1. 新建 version/version.go,声明两个包级变量:
       Version (默认 "dev")
       Commit  (默认 "dev")
  2. dto/health.go:HealthResponse 加 Commit 字段(JSON 输出多一字段)
  3. controller/tts.go:HealthResponse 用 version.Version / version.Commit
     替代硬编码字面量
  4. Dockerfile:加 ARG VERSION=dev ARG COMMIT=dev,
     go build 时通过 -ldflags 注入到 version 包的两个变量
效果:
  - 本地 go build (不传 ldflags) → version=dev commit=dev
  - 开发 build (git describe) → version=v0.2.0-5-g4abcd5 commit=g4abcd5
  - release build (打 tag 后) → version=v0.2.1 commit=<对应 hash>
测试环境(develop 分支,无 tag)显示距离上次 release 几个 commit +
具体 hash;生产环境(main + tag)显示干净 semver。

controller/tts.go

@@ -18,6 +18,7 @@ import (
 	"github.com/volcano-tts/tts-api/middleware"
 	"github.com/volcano-tts/tts-api/setting"
 	"github.com/volcano-tts/tts-api/telemetry"
+	"github.com/volcano-tts/tts-api/version"
 )
 
 var (
@@ -229,7 +230,8 @@ func HealthHandler(w http.ResponseWriter, r *http.Request) {
 	resp := dto.HealthResponse{
 		Status:    status,
 		Service:   "ByteDance TTS to OpenAI API Adapter",
-		Version:   "2.0.0 (v3 API)",
+		Version:   version.Version,
+		Commit:    version.Commit,
 		Uptime:    fmt.Sprintf("%.0f seconds", time.Since(startTime).Seconds()),
 		StartTime: startTime.Format(time.RFC3339),
 		Memory:    collectMemorySnapshot(),