Add support for images to Start-SpectreRecording

[jdhitsolutions]

I'd love the ability to include output from Get-SpectreImage when running an HTML SpectreRecording. This might mean converting the image to base64 and creating an img tag.

[jdhitsolutions]

Curiously, this sort of works if I run the script in VSCode. Although the image doesn't render properly

When I run the same code in Windows Terminal, I get this:

The image displays properly in the console.

[jdhitsolutions]

It looks like the Sixel format is not supported in the VSCode integrated terminal

[trackd]

Sixel works in visual studio code insiders.

Getting it to work through the recording is probably going to require quite a bit of work.

Maybe we could cheat a bit if we detect recording to html and just pass the image data..

Otherwise we would have to implement a sixel decoder as well.