Manually handle Enter and Escape in the Window Renamer (#9730)

## Summary of the Pull Request

In exactly the same fashion as the tab renamer, handle <kbd>Enter</kbd> for committing the rename, and <kbd>Escape</kbd> for dismissing the rename.

## References
* Added in #9662

## PR Checklist
* [x] Closes #9720
* [x] I work here
* [n/a] Tests added/passed
* [n/a] Requires documentation to be updated

## Validation Steps Performed
Played with it - this feels good.

src/cascadia/TerminalApp/TerminalPage.cpp

@@ -2682,4 +2682,26 @@ namespace winrt::TerminalApp::implementation
         // of thing with co_return winrt::make<RenameWindowResult>(false).
     }
 
+    // Method Description:
+    // - Manually handle Enter and Escape for committing and dismissing a window
+    //   rename. This is highly similar to the TabHeaderControl's KeyUp handler.
+    // Arguments:
+    // - e: the KeyRoutedEventArgs describing the key that was released
+    // Return Value:
+    // - <none>
+    void TerminalPage::_WindowRenamerKeyUp(const IInspectable& sender,
+                                           winrt::Windows::UI::Xaml::Input::KeyRoutedEventArgs const& e)
+    {
+        if (e.OriginalKey() == Windows::System::VirtualKey::Enter)
+        {
+            // User is done making changes, close the rename box
+            _WindowRenamerActionClick(sender, nullptr);
+        }
+        else if (e.OriginalKey() == Windows::System::VirtualKey::Escape)
+        {
+            // User wants to discard the changes they made
+            WindowRenamerTextBox().Text(WindowName());
+            WindowRenamer().IsOpen(false);
+        }
+    }
 }

src/cascadia/TerminalApp/TerminalPage.h

@@ -326,7 +326,7 @@ namespace winrt::TerminalApp::implementation
 
         void _WindowRenamerActionClick(const IInspectable& sender, const IInspectable& eventArgs);
         void _RequestWindowRename(const winrt::hstring& newName);
-
+        void _WindowRenamerKeyUp(const IInspectable& sender, winrt::Windows::UI::Xaml::Input::KeyRoutedEventArgs const& e);
 #pragma region ActionHandlers
         // These are all defined in AppActionHandlers.cpp
 #define ON_ALL_ACTIONS(action) DECLARE_ACTION_HANDLER(action);

src/cascadia/TerminalApp/TerminalPage.xaml

@@ -140,6 +140,7 @@
                          ActionButtonClick="_WindowRenamerActionClick">
             <mux:TeachingTip.Content>
                 <TextBox x:Name="WindowRenamerTextBox"
+                         KeyUp="_WindowRenamerKeyUp"
                          Text="{x:Bind WindowName, Mode=OneWay}" />
             </mux:TeachingTip.Content>
         </mux:TeachingTip>