DocumentFormat.OpenXml.Linq namespace-related classes have missing XName fields.

**Describe the bug**
The generated classes in the `DocumentFormat.OpenXml.Linq` namespace (e.g., `W`) are missing certain `XName` fields that were still present in previous versions of the SDK (e.g., 2.19.0). For example, the following fields are missing (among possibly others that I did not see):

- `W.sdtPr`
- `W.sdtEndPr`
- `W.tag`

**To Reproduce**
To reproduce, just try to reference any of the above in your code.

**Observed behavior**
`XName` fields are suddenly no longer generated.

**Expected behavior**
All relevant fields should be generated.

**Desktop (please complete the following information):**
- OS: any
- Office version: any
- .NET Target: any
- DocumentFormat.OpenXml Version: 3.1.1

**Additional context**
3.1.1 is the first release after 3.x that I am trying. I previously used 2.19.0 and possibly 2.20.0. Thus, I don't know exactly when the issue first appeared.

**Edit November 22, 2024**: It turns out the SmartTag-related fields were not part of 2.19.0:

- `W.smartTag`
- `W.smartTagPr`