Improve formatting of lists

List layout adjustments in the SKS LaTeX path: list item spacing and the
surrounding document style tuned in list.py, latex_util.py,
document.sty, and block.k.

Assembled from dev commit f34e66a4dbfb.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

sks/target/latex_util.py

@@ -90,7 +90,7 @@ def offset_space(offset):
     length = offset_length(offset)
     return "" if length == "0pt" else f"\\hspace*{{{length}}}"
 
-def caption_wrapper(element, hpos, bottom_margin=.67, offset=None):
+def caption_wrapper(element, hpos, bottom_margin=0, offset=None):
     # hpos is left, center, right, none (no wrapper), or a length, which
     # becomes the left margin.  The element is a box on a line inside a
     # full-width minipage; \hfill on the empty side pushes it into place.