Show the new theme and notes features in the example

Adds a subsection with its divider, and after \appendix a table and a
figure, so the appendix numbering, table tagging and alt text all have
something exercising them. The table declares its header row, without which
the header cells are tagged TD like any other.

Frame titles are given as \frametitle rather than as the argument to
\begin{frame}, since only the command form is tagged as a heading.

The palette override moves above \usepackage{trantor} so the theme picks it
up, and the notes show both forms: plain \note and \note[item].

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

slides_template/example.tex

@@ -9,28 +9,18 @@
 
 \usepackage{unicode-math}
 \usepackage{graphicx}
+\usepackage{booktabs}
 
-% Font paths must stay inside this directory. LuaTeX fails to resolve a
-% parent-relative Path= and dies with an unhelpful empty-filename error.
-\setsansfont{OpenSans}[
-  Path = fonts/OpenSans/, Extension = .ttf,
-  UprightFont = *-Regular, BoldFont = *-Bold,
-  ItalicFont = *-Italic, BoldItalicFont = *-BoldItalic]
-\setmonofont{RobotoMono}[
-  Path = fonts/RobotoMono/, Extension = .ttf,
-  UprightFont = *-Regular, BoldFont = *-Bold,
-  ItalicFont = *-Italic, BoldItalicFont = *-BoldItalic]
+\input{fonts.tex}
 
 \definecolor{makopurple1}{RGB}{57,39,91}
 \definecolor{makopurple4}{RGB}{124,99,173}
 \definecolor{accent}{RGB}{124,99,173}
+\colorlet{TrantorDark}{makopurple1}
 
 \usepackage{trantor}
 \usepackage{talk-notes}
 
-% trantor's dark panels (section pages and \standout) default to black
-\colorlet{TrantorDark}{makopurple1}
-
 \hypersetup{pdfdisplaydoctitle=true,pdftitle={Presentation Title}}
 
 \renewcommand{\titlelogo}{%
@@ -70,6 +60,8 @@
   \note<1>{Set up the integral before revealing anything else.}
   \note{Mention that this is the Gaussian integral.}
   \note<3->{Once the whole list is up, tie it back to the opening claim.}
+  \note[item]{Check the clock here.}
+  \note[item]{Ask whether anyone has seen the 2099 preprint.}
 \end{frame}
 
 \begin{frame}
@@ -81,6 +73,44 @@
   \note{A note that applies to this whole frame.}
 \end{frame}
 
+\subsection{An Introductory Subsection}
+\subsectionpage
+
+\begin{frame}
+  \frametitle{After the subsection page}
+  Subsections get their own divider, showing the section above the subsection.
+
+  \note{The subsection page is trantor's, not ltx-talk's.}
+\end{frame}
+
+\appendix
 \standout{Example and Data Appendix}
 
+\begin{frame}
+  \frametitle{A table}
+  % without this the header cells are tagged TD like any other
+  \tagpdfsetup{table/header-rows={1}}
+  \begin{tabular}{lrr}
+    \toprule
+    Wiki & Editors & Articles \\
+    \midrule
+    English   & 121{,}000 & 6{,}900{,}000 \\
+    German    &  17{,}000 & 2{,}900{,}000 \\
+    Cebuano   &     150   & 6{,}100{,}000 \\
+    \bottomrule
+  \end{tabular}
+
+  \note{Numbers are made up; the point is that the table is tagged.}
+\end{frame}
+
+\begin{frame}
+  \frametitle{A figure}
+  \includegraphics[width=0.3\linewidth,
+    alt={Community Data Science Collective logo}]{figures/logo.pdf}
+
+  Every figure needs alt text, or the artifact option if it is decoration.
+
+  \note{Alt text reaches the PDF here, unlike under beamer.}
+\end{frame}
+
 \end{document}