NumberBox delayed value propagation after keyboard input

[KillyMXI]

Describe the bug

• It takes two times to leave ui:NumberBox focus for the input value to propagate into binded ViewModel;
• Changing to UpdateSourceTrigger=PropertyChanged makes it behave like is should've behaved with UpdateSourceTrigger=LostFocus.

Seems like UpdateSourceTrigger=LostFocus happens between Text and Value inside the control.

To Reproduce

I made this reproduction:
https://github.com/KillyMXI/wpf-ui-numberbox-issue-repro

• View: Views/Pages/DashboardPage.xaml
• ViewModel: ViewModels/Pages/DashboardViewModel.cs

Expected behavior

• It should not have extra internal propagation step.
• Value and Text should be updated at the same time.
• It should respect UpdateSourceTrigger setting.
  • PropertyChanged - both Text and Value changes notified immediately;
  • LostFocus - both Text and Value changes notified on lost focus.

Extra:
Invalid value should not override text input. Don't ruin user input.
Invalid state should be telegraphed to the user through validation.
When Text is unparseable - Value should probably be NaN.

Screenshots

What is shown:

• ui:TextBox works as expected;
• binding ViewModel string to Text of ui:NumberBox works as expected, but Value is out of sync;
• binding ViewModel number to Value of ui:NumberBox causes extra step needed to fully propagate new value.

OS version

Edition	Windows 10 Pro
Version	22H2
OS build	19045.3930

.NET version

<TargetFramework>net8.0-windows</TargetFramework>

WPF-UI NuGet version

<PackageReference Include="WPF-UI" Version="3.0.0" />

Additional context

This is most likely related to:

• NumberBox not updating displayed value after changing value #216

but observed from the opposite end.