Previewer does not check for presence of bin folder & necessary content

[Mrcubix]

If you remove the bin and obj folder after getting a successful preview (e.g using a previous version of the extension as it's currently broken right now), and try to open another preview, then an exception will occur trying to open a specified assembly;

2023-11-16 18:01:12.532 [info] {"Error":"System.IO.FileNotFoundException: Could not load file or assembly 
'c:\\Users\\tinta\\Documents\\Repo\\C#\\Avalonia\\Examples\\Issues\\Extension\\MalfunctionningPreview\\Malfunctionning-Preview\\bin\\Debug\\net7.0\\Malfunctionning-Preview.dll'. 
The system cannot find the file specified.
File name: '[...]\\Issues\\Extension\\MalfunctionningPreview\\Malfunctionning-Preview\\bin\\Debug\\net7.0\\Malfunctionning-Preview.dll'
   at System.Reflection.Assembly.LoadFile(String path)
   at Avalonia.DesignerSupport.DesignWindowLoader.LoadDesignerWindow(String xaml, String assemblyPath, String xamlFileProjectPath, Double renderScaling)
   at Avalonia.DesignerSupport.Remote.RemoteDesignerEntryPoint.<>c__DisplayClass18_0.<OnTransportMessage>b__0()","Handle":null,"Exception":{"ExceptionType":"FileNotFoundException","Message":"Could not load file or assembly '[...]\\Issues\\Extension\\MalfunctionningPreview\\Malfunctionning-Preview\\bin\\Debug\\net7.0\\Malfunctionning-Preview.dll'. The system cannot find the file specified.","LineNumber":null,"LinePosition":null}}

2023-11-16 18:01:12.532 [info] {"Error":"System.IO.FileNotFoundException: Could not load file or assembly 
'[...]\\Issues\\Extension\\MalfunctionningPreview\\Malfunctionning-Preview\\bin\\Debug\\net7.0\\Malfunctionning-Preview.dll'. 
The system cannot find the file specified.
File name: '[...]\\Issues\\Extension\\MalfunctionningPreview\\Malfunctionning-Preview\\bin\\Debug\\net7.0\\Malfunctionning-Preview.dll'
   at System.Reflection.Assembly.LoadFile(String path)
   at Avalonia.DesignerSupport.DesignWindowLoader.LoadDesignerWindow(String xaml, String assemblyPath, String xamlFileProjectPath, Double renderScaling)
   at Avalonia.DesignerSupport.Remote.RemoteDesignerEntryPoint.<>c__DisplayClass18_0.<OnTransportMessage>b__0()","Handle":null,"Exception":{"ExceptionType":"FileNotFoundException","Message":"Could not load file or assembly '[...]\\Issues\\Extension\\MalfunctionningPreview\\Malfunctionning-Preview\\bin\\Debug\\net7.0\\Malfunctionning-Preview.dll'. The system cannot find the file specified.","LineNumber":null,"LinePosition":null}}

Tested on https://github.com/Mrcubix/MalfunctionningPreview w/ 11.0.5, instead of 11.0.4 that's currently set in Directory.Build.props