fix(tags): Dont consume a space before content tags

[necauqua]

Content tags appeared to be "hugging" the text that preceeds them,
and as it turned out the tag regex was consuming the space, so the
final HTML actually looked like some text<a.., with the text node
not having the final space.

A simple oneline fix

[jackyzha0]

would like to avoid look-behind for regex time complexity reasons, can we just add the space back in rendering?

[necauqua]

I mean this is a simple fixed-length lookbehind, it does not cause issues like that.

Just tried to add the space back in rendering - it's possible, but real ugly, instead of returning a "link" mdast node we can return ["text", "link"], adding the space in a "text" node if there was one.
It should handle consecutive "text" nodes just fine?. But anyway imo the lookbehind is ok and correct - I'll push the text node thingy if you insist on no lookbehinds.

[jackyzha0]

reasonable, i somehow read it as variable length lookbehind