What does the pull request do?

Allows developers to set a custom Width on TimePicker without the content overflowing. Currently, the internal Button has a hardcoded MinWidth from TimePickerThemeMinWidth (242px) that cannot be overridden, preventing compact TimePickers in narrower layouts.

I made a PR to fix the DatePicker here, but I forgot to also update TimePicker. This PR is identical, except it addresses TimePicker instead.

What is the current behavior?

When setting Width="200" on a TimePicker, the content overflows because the internal Button enforces MinWidth=242 regardless of the control's Width setting.

<TimePicker Width="200" />  <!-- Content overflows -->

What is the updated/expected behavior with this PR?

Developers can now create compact TimePickers by setting MinWidth="0":

<TimePicker Width="200" MinWidth="0" />  <!-- Content fits -->

Default behavior is unchanged - TimePickers without explicit MinWidth still use the theme default (242px).

How was the solution implemented?

1. Added MinWidth and MaxWidth setters to the ControlTheme (preserves default appearance).
2. Removed MinWidth from internal Button, changed MaxWidth to use TemplateBinding.

This allows the Button to shrink when the TimePicker's MinWidth is overridden, while maintaining backward compatibility.

How to test this new behavior:

Add to samples/ControlCatalog/Pages/DateTimePickerPage.xaml:

<TextBlock FontSize="18">A TimePicker with custom Width.</TextBlock>
<StackPanel Orientation="Vertical">
    <Border BorderBrush="Red" BorderThickness="2" Width="200" HorizontalAlignment="Left">
        <TimePicker Width="200" MinWidth="0" />
    </Border>
</StackPanel>

Workaround (for developers waiting for this fix)

Until this PR is merged, you can override the theme resources locally:

<Grid>
    <Grid.Resources>
        <x:Double x:Key="TimePickerThemeMinWidth">0</x:Double>
        <x:Double x:Key="TimePickerThemeMaxWidth">1000</x:Double>
    </Grid.Resources>
    
    <TimePicker Width="200" HorizontalAlignment="Stretch" />
</Grid>

Breaking changes

None

Obsoletions / Deprecations

None