XML documentation for SMO objects should have content from the strings files

Today, properties created by codegen do not have proper documentation
Example:

https://docs.microsoft.com/dotnet/api/microsoft.sqlserver.management.smo.database.azureedition?view=sql-smo-160

the XML documentation file included in the nuget package lacks entries for these properties.

To improve the documentation, we should write a tool to merge the C#-generated XML file with content extracted from the SFC attributes on each facet's public properties. Those strings are currently only shown in the SSMS UI for policy-based management.

The strings reside in the strings file, eg:

https://github.com/microsoft/sqlmanagementobjects/blob/f68bac8d8f651ab5415ef53b81c817677e668c28/src/Microsoft/SqlServer/Management/Smo/LocalizableResources.strings#L657

首先检查 codegen 如何生成 XML 文档，以及 SFC 属性如何在 facet 公共属性上定义。阅读 issue 中引用的 Smo/LocalizableResources.strings 条目，并追踪这些字符串如何暴露给 SSMS。完成的标准是有一个工具将生成的 XML 与提取出的属性文档合并，使 NuGet XML 包含生成属性的条目。