txt section numbering, @typeface :middle/:lift and html scale, NewGardinerOmni, html :leading (from dev 9fa469dd74ed)

Section headings under txt are numbered inside a @document only; @typeface
gains :middle and :lift and its :scale now means the same in html and
pdf; NewGardinerOmni ships (OFL 1.1, Mark-Jan Nederhof) and @egyptian /
@chinese replace @cjk; @table :leading and :colsep reach html; kdesc
--typeface help names the flag; @document.txt is a Python class.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

sks/target/target.k

@@ -63,6 +63,7 @@ of this: neither the transforms nor the quoting reach it.
   '   '  |
   ~   __KTEXTNBSP__
   :after_apply
+    phases.txt_insert_section_numbers ;
     phases.txt_format_footnotes ;
     phases.txt_insert_captions ;
     phases.txt_justify_blocks ;
@@ -83,6 +84,7 @@ of this: neither the transforms nor the quoting reach it.
 @@@target ansi | Plain text with ANSI escape sequences for type styles
   :includes txt
   :after_apply
+    phases.txt_insert_section_numbers ;
     phases.txt_format_footnotes ;
     phases.txt_insert_captions ;
     phases.txt_justify_blocks ;