Support custom dashed attributes for 3rd party libs like HTMX, Unpoly, Alpine, etc.

Interested in some CI/devops improvements?

Setting `tagname` as a keyword arg comes through in the html

Rendering text() after comment() on a different line

Tests and Python 3.13

Typing

Indentation preservation with raw

Undesired whitespace before *span* and *a*.

Most of `test_svg.py` fails with Python 3.13, apparently over indentation differences

I run into event loop warnings when running uni tests