Make "Reload" command case-insensitive in Command Palette (#39779)

## Problem
The "Reload" command in the Command Palette was only showing up when
searching with a lowercase 'r' (e.g., "reload") but not with an
uppercase 'R' (e.g., "Reload"). This was inconsistent with the
documentation which references a "Reload" command.

## Solution
Fixed the case-sensitivity issue in `FallbackReloadItem.UpdateQuery()`
by changing the string comparison from case-sensitive to
case-insensitive:

```csharp
// Before
_reloadCommand.Name = query.StartsWith('r') ? "Reload" : string.Empty;

// After
_reloadCommand.Name = query.StartsWith("r", StringComparison.OrdinalIgnoreCase) ? "Reload" : string.Empty;
```

This change makes the Reload command visible when typing either "reload"
or "Reload" in the Command Palette, improving the user experience for
extension developers.

Fixes #39769.

---

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: zadjii-msft <18356694+zadjii-msft@users.noreply.github.com>

src/modules/cmdpal/Microsoft.CmdPal.UI.ViewModels/Commands/FallbackReloadItem.cs

@@ -2,6 +2,7 @@
 // The Microsoft Corporation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
 using Microsoft.CommandPalette.Extensions.Toolkit;
 
 namespace Microsoft.CmdPal.UI.ViewModels.BuiltinCommands;
@@ -20,7 +21,7 @@ internal sealed partial class FallbackReloadItem : FallbackCommandItem
 
     public override void UpdateQuery(string query)
     {
-        _reloadCommand.Name = query.StartsWith('r') ? "Reload" : string.Empty;
+        _reloadCommand.Name = query.StartsWith("r", StringComparison.OrdinalIgnoreCase) ? "Reload" : string.Empty;
         Title = _reloadCommand.Name;
     }
 }