CmdPal: Enable pipe table and emphasis extensions for markdown content (#41989)

## Summary of the Pull Request

This PR enables MarkDig extensions on MarkdownTextBlocks to enable pipe
tables and to enable advanced emphasis (like strikethrough).

- Sets `UsePipeTables` and `UseEmphasisExtras` to true.
- Adds pipe table and HTML table to samples.

<img width="1728" height="1506" alt="image"
src="https://github.com/user-attachments/assets/bf3aae5f-d8cc-492e-91e8-83b507ccca08"
/>


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## PR Checklist

- [x] Closes: #41984
- [ ] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected
- [ ] **Tests:** Added/updated and all pass
- [ ] **Localization:** All end-user-facing strings can be localized
- [ ] **Dev docs:** Added/updated
- [ ] **New binaries:** Added on the required places
- [ ] [JSON for
signing](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ESRPSigning_core.json)
for new binaries
- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
- [ ] [YML for CI
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
for new test projects
- [ ] [YML for signed
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/release.yml)
- [ ] **Documentation updated:** If checked, please file a pull request
on [our docs
repo](https://github.com/MicrosoftDocs/windows-uwp/tree/docs/hub/powertoys)
and link it here: #xxx

<!-- Provide a more detailed description of the PR, other things fixed,
or any additional comments/features here -->
## Detailed Description of the Pull Request / Additional comments

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wherever possible, but list manual validation steps taken as well -->
## Validation Steps Performed

src/modules/cmdpal/ext/SamplePagesExtension/Pages/SampleMarkdownPage.cs

@@ -147,8 +147,47 @@ Result:
 
 \*literally\*
 
+## Tables
+
+### Pipe table
+
+[Markdig - Pipe Table specs](https://github.com/xoofx/markdig/blob/master/src/Markdig.Tests/Specs/PipeTableSpecs.md)
+
+| Right | Left | Default | Center |
+|------:|:-----|---------|:------:|
+|   12  |  12  |    12   |    12  |
+|  123  |  123 |   123   |   123  |
+|    1  |    1 |     1   |     1  |
+
+### HTML table
+
+<table>
+<thead>
+<tr>
+<th style=""text-align: left;"">a</th>
+<th style=""text-align: center;"">b</th>
+<th style=""text-align: right;"">c</th>
+</tr>
+</thead>
+<tbody>
+<tr>
+<td style=""text-align: left;"">0</td>
+<td style=""text-align: center;"">1</td>
+<td style=""text-align: right;"">2</td>
+</tr>
+<tr>
+<td style=""text-align: left;"">3</td>
+<td style=""text-align: center;"">4</td>
+<td style=""text-align: right;"">5</td>
+</tr>
+</tbody>
+</table>
+
+
 ## Advanced Markdown
 
+[Markdig - emphasis extensions](https://github.com/xoofx/markdig/blob/master/src/Markdig.Tests/Specs/EmphasisExtraSpecs.md)
+
 Note: Some syntax which is not standard to native Markdown. They're extensions of the language.
 
 ### Strike-throughs