Code Quality: Reorganze namespaces

[0x5bfa]

Description

Reorganize namespaces. For more information, see Details of Changes

Motivation and Context

I found that there're a lot of namespaces that need to be reorganized and there're namespaces that do not need to be separated and I merged them into the same.

Details of Changes

Previous	New	Rationale
Files.App.Controllers.IJson	Remove	Unused
Files.App.ValueConverters	Files.App.Converters	Same thing
Files.App.AppModels	Files.App.DataModels	Same thing
Files.App.CommandLine	Files.Backend.CommandLine	Be able to be moved to Backend
UserControls/Pane/PreviewPane	UserControls/PreviewPane	No need to be another folder
UserControls' ViewModels(Files.App.ViewModels.*)	Files.App.ViewModels.UserControls	Organized

Validation

• Built and ran the app
• Tested the changes for accessibility

[0x5bfa]

Ready to review :)

[QuaintMako]

LGTM.

[QuaintMako]

@onein528 could you look into the conflicts?

[yaira2]

@d2dyno1 are you okay with these changes?

[d2dyno1]

Might be confusing when using multiple namespaces

[0x5bfa]

As well not include Settings, Properties, Page like AboutSettingsViewModel. This is not accepted(AboutViewModel will be okay).

[d2dyno1]

I'm not a fan of this approach. While I'd agree to shorten longer class names, in this example, the full name is actually necessary.

Someone looking at the code might question themselves: "DynamicViewModel of what? How is it dynamic? Oh, it's for a dialog..."

[0x5bfa]

Then how about Settings.AboutViewModel? I think we should avoid duplication because you can hover on them and look for where it from and what it represents if they have the XAML comment. That's why I changed Properties.PropertiesGeneral to Properties.GeneralPage(although Page is necessary, they didn't have it) and I added ViewModels.UserControls.* instead of putting directly UserControl's ViewModel into ViewModels.*