CmdPal: Fix missing app context menu actions on the main page (#46293)

## Summary of the Pull Request

This PR fixes missing _Pin to ..._ menu items on app search result.

`MainListPage` reuses `AppListItem` instances from the All Apps page,
but their context menus were being built with the main page provider
context instead of the All Apps provider context.


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## PR Checklist

- [x] Closes: #45848
- [x] Closes: #46285
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- [ ] **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
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- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
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- [ ] **Documentation updated:** If checked, please file a pull request
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## Detailed Description of the Pull Request / Additional comments

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## Validation Steps Performed

src/modules/cmdpal/Microsoft.CmdPal.UI/CommandPaletteContextMenuFactory.cs

@@ -4,6 +4,8 @@
 
 using CommunityToolkit.Mvvm.Messaging;
 using ManagedCommon;
+using Microsoft.CmdPal.Ext.Apps;
+using Microsoft.CmdPal.Ext.Apps.Programs;
 using Microsoft.CmdPal.UI.ViewModels;
 using Microsoft.CmdPal.UI.ViewModels.Messages;
 using Microsoft.CmdPal.UI.ViewModels.Services;
@@ -56,6 +58,17 @@ internal sealed partial class CommandPaletteContextMenuFactory : IContextMenuFac
         List<IContextItem> moreCommands = [];
         var itemId = commandItem.Command.Id;
         var providerContext = page.ProviderContext;
+
+        // AppListItems can be surfaced on the main page even though they still
+        // belong to the All Apps provider.
+        // MainListPage only returns our in-proc wrappers/items.
+        if (providerContext.ProviderId != AllAppsCommandProvider.WellKnownId &&
+            page is ListViewModel { IsMainPage: true } &&
+            commandItem.Model.Unsafe is AppListItem)
+        {
+            providerContext = _topLevelCommandManager.LookupProvider(AllAppsCommandProvider.WellKnownId)?.GetProviderContext() ?? providerContext;
+        }
+
         var supportsPinning = providerContext.SupportsPinning;
 
         if (supportsPinning &&