CmdPal: Update Extension SDK docs link to Microsoft Learn (#44517)

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fix/what does it change/how was it tested
  (even manually, if necessary)? -->
## Summary of the Pull Request
Update CmdPal SDK docs links to point to Microsoft Learn as requested in
#40994.

 

  <!-- Please review the items on the PR checklist before submitting-->
  ## PR Checklist

  - [x] Closes: #40994
<!-- - [ ] Closes: #yyy (add separate lines for additional resolved
issues) -->
- [ ] **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
  - [x] **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
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 ## Detailed Description of the Pull Request / Additional comments
  Updated links in:
    - src/modules/cmdpal/Microsoft.CmdPal.UI/Settings/GeneralPage.xaml
    - src/modules/cmdpal/extensionsdk/README.md

Note: The issue proposes linking directly to “Command Palette /
Developer Docs / Extensibility overview” on
Learn. I noticed the project often uses fwlink/aka.ms redirects instead
of direct Learn URLs. If creating a
redirect is preferred (or if I can create one), let me know and I’ll
update the links accordingly.

<!-- Describe how you validated the behavior. Add automated tests
wherever possible, but list manual validation
  steps taken as well -->
  ## Validation Steps Performed
Manually verified that the links resolve to the Microsoft Learn Command
Palette extensibility overview.

---------

Co-authored-by: Niels Laute <niels.laute@live.nl>

src/modules/cmdpal/Microsoft.CmdPal.UI/Settings/GeneralPage.xaml

@@ -106,7 +106,7 @@
                             <controls:SettingsCard HorizontalContentAlignment="Left" ContentAlignment="Left">
                                 <StackPanel Margin="-12,0,0,0" Orientation="Vertical">
                                     <HyperlinkButton x:Uid="Settings_GeneralPage_About_GithubLink_Hyperlink" NavigateUri="https://go.microsoft.com/fwlink/?linkid=2310837" />
-                                    <HyperlinkButton x:Uid="Settings_GeneralPage_About_SDKDocs_Hyperlink" NavigateUri="https://go.microsoft.com/fwlink/?linkid=2310639" />
+                                    <HyperlinkButton x:Uid="Settings_GeneralPage_About_SDKDocs_Hyperlink" NavigateUri="https://aka.ms/cmdpalextensions-devdocs" />
                                 </StackPanel>
                             </controls:SettingsCard>
                         </controls:SettingsExpander.Items>

src/modules/cmdpal/extensionsdk/README.md

@@ -7,7 +7,7 @@ Palette, and use the "Create a new extension" command. That will set up a
 project for you, with the packaging, dependencies, and basic program structure
 ready to go.
 
-To view the full docs, you can head over to [our docs site](https://go.microsoft.com/fwlink/?linkid=2310639)
+To view the full docs, you can head over to [our docs site](https://aka.ms/cmdpalextensions-devdocs)
 
 There are samples of just about everything you can do in [the samples project].
 Head over there to see basic usage of the APIs.