Add ability to show block title over the border

[eugener]

The title could be shown either on top or bottom of the block. Here one example of such UI

The API might look like the following

var style = lipgloss.NewStyle().
    BorderStyle(lipgloss.NormalBorder()).
    BorderForeground(lipgloss.Color("63")).
    Title(lipgloss.Top, "Title")

There is also a need to change the title dynamically

  style.SetTitle((lipgloss.Top, "New Title"))

Titles which do not fit the width of the block can be automatically truncated at the front or back. The fact of truncation can be represented by adding … character

[meowgorithm]

Implementation specifics aside, this seems like a good addition, though it may also be better off as a standalone component. If we were to add it to the library we'd also need to be able to set colors as well as the option to have both a top and bottom label simultaneously, and potential horizontal padding on the label.

If this is something you need right now here's a basic implementation you can start from: https://gist.github.com/meowgorithm/1777377a43373f563476a2bcb7d89306

[eugener]

This is pretty similar to what I had to implement within the app I'm working on. Addition of Title API to styles would make it no-brainer. Title colors and horizontal alignment (left, center,right) would be a welcome addition too!

[eugener]

@meowgorithm Please take a look at related PR #97. Hopefully, with few iterations, this API can become a part of the library

[meowgorithm]

Thanks @eugener. I’m on holiday for the next few weeks and will look at it when I’m back. I do think this is a common enough request that we should accommodate it.

[greenm01]

I would also like to add a title to my border, similar to TermUI: https://raw.githubusercontent.com/gizak/termui/master/_assets/demo.gif

Thanks!