[CmdPal]Fix Calc and Command extension fallback command icons (#38146)

Author: jaimecbernardo

src/modules/cmdpal/Exts/Microsoft.CmdPal.Ext.Calc/CalculatorCommandProvider.cs

@@ -141,6 +141,7 @@ public override ICommandResult Invoke()
 internal sealed partial class FallbackCalculatorItem : FallbackCommandItem
 {
     private readonly CopyTextCommand _copyCommand = new(string.Empty);
+    private static readonly IconInfo _cachedIcon = IconHelpers.FromRelativePath("Assets\\Calculator.svg");
 
     public FallbackCalculatorItem()
         : base(new NoOpCommand(), Resources.calculator_title)
@@ -149,7 +150,7 @@ public FallbackCalculatorItem()
         _copyCommand.Name = string.Empty;
         Title = string.Empty;
         Subtitle = Resources.calculator_placeholder_text;
-        Icon = new IconInfo("\ue8ef"); // Calculator
+        Icon = _cachedIcon;
     }
 
     public override void UpdateQuery(string query)

src/modules/cmdpal/exts/Microsoft.CmdPal.Ext.Shell/FallbackExecuteItem.cs

@@ -20,7 +20,7 @@ public FallbackExecuteItem(SettingsManager settings)
         Title = string.Empty;
         _executeItem.Name = string.Empty;
         Subtitle = Properties.Resources.generic_run_command;
-        Icon = new IconInfo("\uE756");
+        Icon = Icons.RunV2; // Defined in Icons.cs and contains the execute command icon.
     }
 
     public override void UpdateQuery(string query)