feat(标准版本): 修复裁剪字形并完善版本兼容

ofdgo_xml.go

@@ -0,0 +1,48 @@
+// Copyright 2025-2026 肖其顿 (XIAO QI DUN)
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ofdgo
+
+// 旧版与2016版OFD命名空间
+const (
+	ofdNamespaceLegacy = "http://www.ofdspec.org"
+	ofdNamespace2016   = "http://www.ofdspec.org/2016"
+)
+
+// 未声明、未知、旧版及2016版OFD命名空间，不限制已知内容的读取
+const (
+	ofdXMLUnqualified ofdXMLNamespace = iota
+	ofdXMLUnknown
+	ofdXMLLegacy
+	ofdXML2016
+)
+
+// ofdXMLNamespace 标识XML节点采用的OFD命名空间
+type ofdXMLNamespace uint8
+
+// classifyOFDNamespace 识别OFD命名空间，未声明与未知版本分别处理
+// 入参: namespace XML命名空间
+// 返回: ofdXMLNamespace 命名空间类别
+func classifyOFDNamespace(namespace string) ofdXMLNamespace {
+	switch namespace {
+	case "":
+		return ofdXMLUnqualified
+	case ofdNamespaceLegacy:
+		return ofdXMLLegacy
+	case ofdNamespace2016:
+		return ofdXML2016
+	default:
+		return ofdXMLUnknown
+	}
+}