[Revamp pipeline thread handling] Enable proper terminal color support on the host

[SydneyhSmith]

PowerShell achieves terminal color support by communicating to the host a PSObject with properties with certain names (because that was how the awareness was added to PowerShell's own host capabilities).

This is available in PSES today through this:

PowerShellEditorServices/src/PowerShellEditorServices/Services/PowerShellContext/Session/Host/EditorServicesPSHost.cs

Lines 82 to 237 in 4fa0346

	internal class ConsoleColorProxy
	{
	private EditorServicesPSHostUserInterface _hostUserInterface;
	internal ConsoleColorProxy(EditorServicesPSHostUserInterface hostUserInterface)
	{
	if (hostUserInterface == null) throw new ArgumentNullException("hostUserInterface");
	_hostUserInterface = hostUserInterface;
	}
	/// <summary>
	/// The Accent Color for Formatting
	/// </summary>
	public ConsoleColor FormatAccentColor
	{
	get
	{ return _hostUserInterface.FormatAccentColor; }
	set
	{ _hostUserInterface.FormatAccentColor = value; }
	}
	/// <summary>
	/// The Accent Color for Error
	/// </summary>
	public ConsoleColor ErrorAccentColor
	{
	get
	{ return _hostUserInterface.ErrorAccentColor; }
	set
	{ _hostUserInterface.ErrorAccentColor = value; }
	}
	/// <summary>
	/// The ForegroundColor for Error
	/// </summary>
	public ConsoleColor ErrorForegroundColor
	{
	get
	{ return _hostUserInterface.ErrorForegroundColor; }
	set
	{ _hostUserInterface.ErrorForegroundColor = value; }
	}
	/// <summary>
	/// The BackgroundColor for Error
	/// </summary>
	public ConsoleColor ErrorBackgroundColor
	{
	get
	{ return _hostUserInterface.ErrorBackgroundColor; }
	set
	{ _hostUserInterface.ErrorBackgroundColor = value; }
	}
	/// <summary>
	/// The ForegroundColor for Warning
	/// </summary>
	public ConsoleColor WarningForegroundColor
	{
	get
	{ return _hostUserInterface.WarningForegroundColor; }
	set
	{ _hostUserInterface.WarningForegroundColor = value; }
	}
	/// <summary>
	/// The BackgroundColor for Warning
	/// </summary>
	public ConsoleColor WarningBackgroundColor
	{
	get
	{ return _hostUserInterface.WarningBackgroundColor; }
	set
	{ _hostUserInterface.WarningBackgroundColor = value; }
	}
	/// <summary>
	/// The ForegroundColor for Debug
	/// </summary>
	public ConsoleColor DebugForegroundColor
	{
	get
	{ return _hostUserInterface.DebugForegroundColor; }
	set
	{ _hostUserInterface.DebugForegroundColor = value; }
	}
	/// <summary>
	/// The BackgroundColor for Debug
	/// </summary>
	public ConsoleColor DebugBackgroundColor
	{
	get
	{ return _hostUserInterface.DebugBackgroundColor; }
	set
	{ _hostUserInterface.DebugBackgroundColor = value; }
	}
	/// <summary>
	/// The ForegroundColor for Verbose
	/// </summary>
	public ConsoleColor VerboseForegroundColor
	{
	get
	{ return _hostUserInterface.VerboseForegroundColor; }
	set
	{ _hostUserInterface.VerboseForegroundColor = value; }
	}
	/// <summary>
	/// The BackgroundColor for Verbose
	/// </summary>
	public ConsoleColor VerboseBackgroundColor
	{
	get
	{ return _hostUserInterface.VerboseBackgroundColor; }
	set
	{ _hostUserInterface.VerboseBackgroundColor = value; }
	}
	/// <summary>
	/// The ForegroundColor for Progress
	/// </summary>
	public ConsoleColor ProgressForegroundColor
	{
	get
	{ return _hostUserInterface.ProgressForegroundColor; }
	set
	{ _hostUserInterface.ProgressForegroundColor = value; }
	}
	/// <summary>
	/// The BackgroundColor for Progress
	/// </summary>
	public ConsoleColor ProgressBackgroundColor
	{
	get
	{ return _hostUserInterface.ProgressBackgroundColor; }
	set
	{ _hostUserInterface.ProgressBackgroundColor = value; }
	}
	}
	/// <summary>
	/// Return the actual console host object so that the user can get at
	/// the unproxied methods.
	/// </summary>
	public override PSObject PrivateData
	{
	get
	{
	if (hostUserInterface == null) return null;
	return _consoleColorProxy ?? (_consoleColorProxy = PSObject.AsPSObject(new ConsoleColorProxy(hostUserInterface)));
	}
	}
	private PSObject _consoleColorProxy;

We need to restore this functionality in the new integrated console.

[rjmholt]

/cc @SteveL-MSFT who knows more information about what's required to implement to make this work

[rjmholt]

To solve in #1459

[rjmholt]

I don't seem to be able to make this feature work in the ConsoleHost:

@SteveL-MSFT is this still something we need to implement?

[andyleejordan]

Closing as duplicate.