fix(编辑能力): 修正文字编辑，统一元数据命名

ofdgo_writer.go

@@ -1242,14 +1242,14 @@ func (x *ofdXML) object(object GraphicObject, root bool) {
 	switch object.Type {
 	case "TextObject", "Text":
 		obj := object.TextObject
-		metadata, err := obj.layoutMetadata()
+		metadata, err := obj.textMetadata()
 		if err != nil {
 			x.err = err
 			return
 		}
 		if metadata != "" {
-			attrs.add("xmlns:ofdgo", textLayoutNamespace)
-			attrs.add("ofdgo:Layout", metadata)
+			attrs.add("xmlns:ofdgo", textNamespace)
+			attrs.add("ofdgo:Text", metadata)
 		}
 		attrs.add("ID", obj.ID)
 		attrs.add("DrawParam", obj.DrawParam)