Report the exact trace where a rendering error occurred

[volfpeter]

Trace back the error raised in HTMY._render_one() all the way to the root component and report the whole trace to help debugging.

[volfpeter]

There were some changes since this feature request came in (maybe on Reddit). There are 2 renderers now: the default one which is more performant but also more complex, and the baseline renderer, which is very simple but less performant. To not hurt the performance of the default renderer, it may be a good idea to only have this feature in the baseline renderer, and users could fall back to that when they need to do debugging. This would be good practice anyway, because the baseline renderer's correctness is easy to validate, so it's better suited to debugging.