memo_template: add new article-class memo template

Replaces the assignment_template with a memo-format template based
on the article class. The look-and-feel is ported from the old
cdsc-memo chapterstyle in cdsc-memoir.sty: a single-line "TITLE
[hfill] AUTHOR" header and sans-serif uppercase section headings.

Like the migrated paper_template, this builds with lualatex and
produces a tagged, PDF/UA-2 compliant PDF. verapdf --flavour ua2:
0 failures, 1723 passed rules.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

memo_template/cdsc-memo.sty

@@ -0,0 +1,90 @@
+% Memo-style page layout for CDSC documents.
+%
+% Article-class equivalent of the old cdsc-memo chapterstyle that
+% lived in cdsc-memoir.sty. Targets the standard `article' class so
+% the LaTeX tagging-project can produce tagged, accessible PDFs.
+%
+% Look-and-feel: sans-serif uppercase title and author on a single
+% line, sans-serif uppercase section headings, no paragraph indent,
+% and a small-caps "page/total" footer.
+%
+% Copyright 2009-2026 Benjamin Mako Hill <mako@atdot.cc>
+% Copyright 2008-2009 Kieran Healy <kjhealy@soc.duke.edu>
+
+% Distributed as free software under the GNU GPL v3
+
+\usepackage{lastpage}
+\usepackage{xcolor}
+
+%%% Page style: empty header; "page/total" centered in the footer.
+\usepackage{fancyhdr}
+\setlength{\headheight}{14.5pt}
+\addtolength{\topmargin}{-2.5pt}
+
+\fancypagestyle{cdsc-page-memo}{%
+  \fancyhf{}%
+  \fancyfoot[C]{\scshape\thepage/\pageref*{LastPage}}%
+  \renewcommand{\headrulewidth}{0pt}%
+}
+
+% Variant with git revision info in the footer (requires the vc package).
+\fancypagestyle{cdsc-page-memo-git}{%
+  \fancyhf{}%
+  \fancyfoot[C]{\texttt{\footnotesize\textcolor{BrickRed}{git revision \VCRevision\ on \VCDateTEX}}}%
+  \renewcommand{\headrulewidth}{0pt}%
+}
+
+\pagestyle{cdsc-page-memo}
+
+%%% Section headings: large sans-serif bold uppercase, with the
+%%% tight before/after spacing the original memo style used.
+\usepackage{titlesec}
+
+\titleformat{\section}
+  {\normalsize\sffamily\bfseries\MakeUppercase}{\thesection.}{0.5em}{}
+\titlespacing*{\section}{0pt}{*1.5}{1pt}
+
+\titleformat{\subsection}
+  {\small\sffamily\bfseries\MakeUppercase}{\thesubsection.}{0.5em}{}
+\titlespacing*{\subsection}{0pt}{*1}{1pt}
+
+\titleformat{\subsubsection}[runin]
+  {\footnotesize\sffamily\bfseries}{\thesubsubsection.}{0.5em}{}[\hskip 0.5em]
+
+% By default, suppress section numbering. To enable numbered sections
+% and subsections, comment the line below and uncomment the alternative.
+\setcounter{secnumdepth}{0}
+% \setcounter{secnumdepth}{2}
+
+%%% Title block: "TITLE [...] AUTHOR" on a single line, no date.
+\usepackage{titling}
+
+\renewcommand{\maketitle}{%
+  \par\noindent\footnotesize\puB\par
+  {\large\sffamily\bfseries\MakeUppercase\thetitle}\hfill
+  {\large\sffamily\MakeUppercase\theauthor}%
+  \par\vskip 0.7em%
+}
+
+%% \published{...}: a note about publication status, printed in small
+%% type at the very top of the title block.
+\newcommand{\puB}{}
+\newcommand{\published}[1]{\gdef\puB{#1}}
+
+%%% List spacing
+\usepackage{enumitem}
+\setlist{topsep=0pt, partopsep=0pt}
+
+%%% Caption font
+\usepackage{caption}
+\captionsetup{font=small}
+
+%%% No paragraph indent (memos use a blank-line paragraph break style).
+\setlength{\parindent}{0pt}
+
+%%% Footnote symbol command (for \thanks{} footnotes that should not
+%%% have a numeric mark). Use as \symbolfootnote[0]{Footnote text}.
+\long\def\symbolfootnote[#1]#2{\begingroup%
+  \def\thefootnote{\fnsymbol{footnote}}\footnote[#1]{#2}\endgroup}
+
+\endinput