init: scaffold OPENBUREAU site with shibui-derived theme

- Hugo site for openbureau.ch (Deutsch, i18n-ready for EN/IT)
- Theme themes/openbureau/ = local copy of shibui, customized via
  site-level layouts and assets to keep the theme reference clean
- Editorial typography stack: Newsreader serif body, Space Grotesk
  display, Inter for listings, IBM Plex Mono for technical meta
- Content structure: library/ (Theorie, Büroführung, Software) with
  manifest and colophon at root; software is a library category, not
  a separate top-level
- Three views over one source: Journal (chronological home),
  Library (atlas grouped by section + tag cloud), single articles

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

themes/openbureau/layouts/_partials/terms.html

@@ -0,0 +1,22 @@
+{{- /*
+For a given taxonomy, renders a list of terms assigned to the page.
+
+@context {page} page The current page.
+@context {string} taxonomy The taxonomy.
+
+@example: {{ partial "terms.html" (dict "taxonomy" "tags" "page" .) }}
+*/}}
+
+{{- $page := .page }}
+{{- $taxonomy := .taxonomy }}
+
+{{- with $page.GetTerms $taxonomy }}
+  {{- $label := (index . 0).Parent.LinkTitle }}
+  <div class="terms-list">
+    <ul>
+      {{- range . }}
+        <li><a href="{{ .RelPermalink }}">#{{ .LinkTitle }}</a></li>
+      {{- end }}
+    </ul>
+  </div>
+{{- end }}