refactor: split backend transport and domain modules

internal/server/middleware/request.go

@@ -0,0 +1,18 @@
+package middleware
+
+import (
+	"github.com/gin-gonic/gin"
+	"github.com/google/uuid"
+)
+
+func RequestMeta() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		requestID := c.GetHeader("X-Request-Id")
+		if requestID == "" {
+			requestID = uuid.NewString()
+		}
+		c.Header("X-Request-Id", requestID)
+		c.Set("request_id", requestID)
+		c.Next()
+	}
+}