Hugo site: layouts, config and pilot content

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01YDRjtmAiNpo5mK5N3d7QwZ

layouts/_partials/letters.html

@@ -0,0 +1,14 @@
+{{/* alphabetical index of pages, grouped by first character of the title */}}
+{{ $groups := dict }}
+{{ range . }}
+  {{ $l := upper (substr .Title 0 1) }}
+  {{ if not (findRE `^[A-Z]$` $l) }}{{ $l = "#" }}{{ end }}
+  {{ $groups = merge $groups (dict $l ((index $groups $l | default slice) | append .)) }}
+{{ end }}
+<p class="letters">
+  {{ range $l, $_ := $groups }}<a href="#letter-{{ $l | urlize }}">{{ $l }}</a> {{ end }}
+</p>
+{{ range $l, $pages := $groups }}
+<h2 id="letter-{{ $l | urlize }}">{{ $l }}</h2>
+{{ partial "page-list.html" $pages }}
+{{ end }}