fix: 嵌入式前端正确服务world.json等静态文件

- 修复/install路由返回登录页问题
- checkConfigFile只检查数据目录
- setupEmbeddedFrontend正确响应项目目录下文件

backend/cmd/main.go

@@ -261,17 +261,29 @@ func setupEmbeddedFrontend(r *gin.Engine) {
 		return
 	}
 
-	r.NoRoute(func(c *gin.Context) {
-		if c.Request.Method == "GET" && !strings.HasPrefix(c.Request.URL.Path, "/api/") {
-			serveIndexHTML(c, string(indexHTML))
-			return
-		}
-		c.JSON(404, gin.H{"error": "not found"})
-	})
+	fileServer := http.FileServer(http.FS(distFS))
 
 	r.GET("/assets/*filepath", func(c *gin.Context) {
 		c.FileFromFS(c.Request.URL.Path, http.FS(distFS))
 	})
+
+	r.GET("/*filepath", func(c *gin.Context) {
+		path := c.Param("filepath")
+		if path == "" || path == "/" {
+			serveIndexHTML(c, string(indexHTML))
+			return
+		}
+		path = strings.TrimPrefix(path, "/")
+
+		f, err := distFS.Open(path)
+		if err == nil {
+			f.Close()
+			fileServer.ServeHTTP(c.Writer, c.Request)
+			return
+		}
+
+		serveIndexHTML(c, string(indexHTML))
+	})
 }
 
 func serveIndexHTML(c *gin.Context, indexHTML string) {