feat(api): enhance public APK endpoint to return semantic version from OTA bundle

The PublicLatestAPK endpoint now reads the expoConfig.json from the OTA bundle
to extract the actual semantic version (expo.version) instead of returning
the runtimeVersion as the version name. Falls back to runtimeVersion if
expoConfig.json is not available.

internal/handlers/handlers.go

@@ -300,9 +300,18 @@ func (h *Handler) PublicLatestAPK(w http.ResponseWriter, r *http.Request) {
 		writeJSON(w, http.StatusNotFound, map[string]any{"error": "No APK available"})
 		return
 	}
+
+	// versionName 优先从同 runtimeVersion 的 OTA bundle 里读取 expoConfig.json
+	// （CI 在 publish OTA 时会把 expoConfig.json 打入 zip）
+	versionName := h.svc.GetAPKVersionName(apk.RuntimeVersion)
+	if versionName == "" {
+		// 兜底：没有 expoConfig 时退回 runtimeVersion（不应该发生，但保底）
+		versionName = apk.RuntimeVersion
+	}
+
 	resp := model.LatestAPKResponse{
 		RuntimeVersion: apk.RuntimeVersion,
-		VersionName:    apk.RuntimeVersion,
+		VersionName:    versionName,
 		Size:           apk.Size,
 		DownloadURL:    fmt.Sprintf("%s/api/apk/download?runtimeVersion=%s", h.svc.Hostname(), apk.RuntimeVersion),
 		CreatedAt:      apk.CreatedAt.Format(time.RFC3339),