This pull request introduces a new method, RestoreFrameless, to the AxisManager class. Its purpose is to revert the frameless state by restoring the visibility of the axes and title. Additionally, corresponding changes have been made in the LayoutManager and Plot classes to expose this functionality at higher levels.

• Fix Frameless: how to "undo" frameless view? #4804

Changes Made

AxisManager.cs

Added RestoreFrameless(bool showTitle = true) Method:
This new method sets all X and Y axes’ IsVisible property to true, effectively reverting the state applied by Frameless(). The title's visibility is controlled by an optional parameter.

/// <summary>
/// Reverts the frameless state by making all axes visible.
/// </summary>
/// <param name="showTitle">Optional: if true, the title is also shown; default is false.</param>
public void RestoreFrameless(bool showTitle = false)
{
    XAxes.ForEach(x => x.IsVisible = true);
    YAxes.ForEach(x => x.IsVisible = true);
    Title.IsVisible = showTitle;
}

LayoutManager.cs

Added RestoreFrameless() Method:
This method calls the new RestoreFrameless on the plot’s axes. This ensures that users who applied a frameless layout via the LayoutManager can now revert the change.

/// <summary>
/// Reverts the frameless layout by restoring the visibility of axes.
/// </summary>
public void RestoreFrameless()
{
    Plot.Axes.RestoreFrameless();
}

Plot.cs

Added ShowAxesAndGrid(bool showTitle = true) Helper Method:
This method reverses the frameless state by calling RestoreFrameless on the AxisManager and then re-enables grid visibility.

/// <summary>
/// Restore visibility for axes and grid (revert frameless settings).
/// </summary>
public void ShowAxesAndGrid(bool showTitle = false)
{
    Axes.RestoreFrameless(showTitle);
    ShowGrid();
}

Example to undo the frameless operation:

myPlot.Layout.RestoreFrameless();