chore: 初始化 TFS 2013 工作项批量导入工具集

- TfsExcelImporter: WinForms 桌面版，走 TFS Client OM（本环境 wit REST 路由 404，OM 是唯一可行通道）
- tfs_import.py: REST 版命令行导入器，供 wit 接口可用的 TFS 实例使用
- templates: Excel 导入模板及其 OOXML 源部件
- README: 两套工具定位、配置、环境坑点与验证方式
- 真实台账与本机工作笔记不入库，仅提交 work_items.example.csv 说明列结构

TfsExcelImporter.sln

@@ -0,0 +1,16 @@
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "TfsExcelImporter", "TfsExcelImporter\TfsExcelImporter.csproj", "{3B7A2C10-9D4E-4F6B-8A21-5C0D7E9F1A44}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{3B7A2C10-9D4E-4F6B-8A21-5C0D7E9F1A44}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{3B7A2C10-9D4E-4F6B-8A21-5C0D7E9F1A44}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{3B7A2C10-9D4E-4F6B-8A21-5C0D7E9F1A44}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{3B7A2C10-9D4E-4F6B-8A21-5C0D7E9F1A44}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+EndGlobal