fix: accept openai x-stainless-* header to fix CORS error

backend/internal/server/middleware/cors.go

@@ -70,7 +70,15 @@ func CORS(cfg config.CORSConfig) gin.HandlerFunc {
 			}
 		}
 
-		c.Writer.Header().Set("Access-Control-Allow-Headers", "Content-Type, Content-Length, Accept-Encoding, X-CSRF-Token, Authorization, accept, origin, Cache-Control, X-Requested-With, X-API-Key")
+		allowHeaders := []string{"Content-Type", "Content-Length", "Accept-Encoding", "X-CSRF-Token", "Authorization", "accept", "origin", "Cache-Control", "X-Requested-With", "X-API-Key"}
+
+		// openai node sdk
+		openAIProperties := []string{"lang", "package-version", "os", "arch", "retry-count", "runtime", "runtime-version", "async", "helper-method", "poll-helper", "custom-poll-interval", "timeout"}
+		for _, prop := range openAIProperties {
+			allowHeaders = append(allowHeaders, "x-stainless-"+prop)
+		}
+
+		c.Writer.Header().Set("Access-Control-Allow-Headers", strings.Join(allowHeaders, ", "))
 		c.Writer.Header().Set("Access-Control-Allow-Methods", "POST, OPTIONS, GET, PUT, DELETE, PATCH")
 
 		// 处理预检请求