[CmdPal] Replaced ellipsis button with 'More' label + shortcut textblock (#39838)

This PR improves the command bar UI in the command palette.
- Replaced ellipses "..." with a "More" label (can be changed to
something else. Maybe "Actions" or "Commands")
- Added a textblock for Ctrl + K shortcut
- Removed tooltip that showed Ctrl + K shortcut when hovering over
previous "..."

Special Note:
- The InfoBar.Severity binding was temporarily commented out because of
a built-time error even though 'State' property is present in the
ViewModel. Happy to revisit this if the team can help/confirm the
intended binding context/behavior

Before change:

![image](https://github.com/user-attachments/assets/5bcb171b-7c09-4fce-a39e-38c5ac8988e3)

After change:

![added_cmdpal_label](https://github.com/user-attachments/assets/38d1ccd8-3d39-42d2-9c15-79028d2018e5)

Closes #39501

---------

Co-authored-by: Michael Jolley <mike@baldbeardedbuilder.com>

src/modules/cmdpal/Microsoft.CmdPal.UI/Controls/CommandBar.xaml

@@ -200,12 +200,45 @@
                 x:Name="MoreCommandsButton"
                 x:Uid="MoreCommandsButton"
                 Padding="4"
-                Content="{ui:FontIcon Glyph=,
-                                      FontSize=16}"
                 Style="{StaticResource SubtleButtonStyle}"
                 Tapped="MoreCommandsButton_Tapped"
                 ToolTipService.ToolTip="Ctrl+K"
-                Visibility="{x:Bind ViewModel.ShouldShowContextMenu, Mode=OneWay}" />
+                Visibility="{x:Bind ViewModel.ShouldShowContextMenu, Mode=OneWay}">
+                <StackPanel Orientation="Horizontal" Spacing="8">
+                    <TextBlock
+                        VerticalAlignment="Center"
+                        Style="{StaticResource CaptionTextBlockStyle}"
+                        Text="More" />
+                    <StackPanel Orientation="Horizontal" Spacing="2">
+                        <Border
+                            Padding="4,2,4,2"
+                            VerticalAlignment="Center"
+                            Background="{ThemeResource SubtleFillColorSecondaryBrush}"
+                            BorderBrush="{ThemeResource DividerStrokeColorDefaultBrush}"
+                            BorderThickness="1"
+                            CornerRadius="4">
+                            <TextBlock
+                                CharacterSpacing="4"
+                                FontSize="10"
+                                Foreground="{ThemeResource TextFillColorSecondaryBrush}"
+                                Text="Ctrl" />
+                        </Border>
+                        <Border
+                            Padding="4,2,4,2"
+                            VerticalAlignment="Center"
+                            Background="{ThemeResource SubtleFillColorSecondaryBrush}"
+                            BorderBrush="{ThemeResource DividerStrokeColorDefaultBrush}"
+                            BorderThickness="1"
+                            CornerRadius="4">
+                            <TextBlock
+                                VerticalAlignment="Center"
+                                FontSize="10"
+                                Foreground="{ThemeResource TextFillColorSecondaryBrush}"
+                                Text="K" />
+                        </Border>
+                    </StackPanel>
+                </StackPanel>
+            </Button>
         </StackPanel>
     </Grid>
 </UserControl>