[Suggestion] When InfoElement.ShowClearButton is enabled, the Clear button always occupies a fixed width

Describe the bug

This issue(https://github.com/HandyOrg/HandyControl/issues/1489) has not been resolved. We should set a fixed width for the Clear Button.

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Fixed:

1. [Fixed width mode] The input box always retains the position of the Clear button. Although the input space is reduced, the layout remains unchanged.

This is my solution:
https://github.com/CodingOctocat/Firefly/blob/master/Firefly/Styles/FixedHandyControlTextBoxPlusTemplate.xaml
https://github.com/CodingOctocat/Firefly/blob/master/Firefly/Styles/FixedHandyControlSearchBarPlusTemplate.xaml
https://github.com/CodingOctocat/Firefly/blob/master/Firefly/Styles/FixedHandyControlComboBoxEditableLeftTemplate.xaml

2. [Overlay mode] Another solution is to have the Clear button cover the top, but if the user wants to select text from the right, they will click on the Clear button. So I think [Fixed width mode] is better.
   (By the way, This is HandyControls 3.6.0 behavior)

Steps to reproduce the bug

Create a input control with InfoElement.ShowClearButton or see the HandyControl Demo.

Expected behavior

No response

Screenshots

No response

NuGet package version

HandyControl 3.5.1

IDE

Visual Studio 2022

Framework type

.Net 9.0

Windows version

Windows 11 (22000)

Additional context

No response

Start with the HandyControl Demo and controls using InfoElement.ShowClearButton, then compare their templates with the referenced FixedHandyControlTextBoxPlusTemplate.xaml, FixedHandyControlSearchBarPlusTemplate.xaml, and FixedHandyControlComboBoxEditableLeftTemplate.xaml files. Done means the Clear button keeps a fixed position when enabled without preventing normal text selection.