Fix CardExpander height to enable ScrollViewer functionality

[Just-Silver]

Pull request type

• Update
• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes

What is the current behavior?

The CardExpander template defines the content row as Height="Auto" (line 117 in CardExpander.xaml), which causes the content area to grow unbounded regardless of available space. This prevents ScrollViewer from working — wrapping content in ScrollViewer has no effect because the parent Grid never constrains height.

What is the new behavior?

• Changed CardExpander.xaml content row from Height="Auto" to Height="*"
• This matches WPF's native Expander behavior, allowing content to fill available space and enabling scrolling when content overflows

Other information

Before: Content row uses Height="Auto", content grows infinitely, ScrollViewer has no effect.

After: Content row uses Height="*", content is constrained to available space, ScrollViewer works correctly.

-                            <RowDefinition Height="Auto" />
+                            <RowDefinition Height="*" />