feat(IFK-11): migrate from Congo to HugoBlox with custom layouts

- Remove Congo theme submodule, add Hugo modules (blox-core)
- Custom baseof/single/home/list layouts (no Tailwind build needed)
- Newsreader serif font preserved throughout
- Agiliton lime/emerald brand colors
- All 7 shortcodes preserved (world-map, charts, stats, etc.)
- Multilingual EN/DE/FR with i18n files
- Self-hosted fonts, no external CSS dependencies
- Wide content layout, clean research-publication aesthetic

Reference: metaconscious.org, matteocourthoud.github.io

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

layouts/_default/single.html

@@ -0,0 +1,63 @@
+{{ define "main" }}
+<article class="prose-lg max-w-2xl mx-auto py-12 px-4">
+  <header class="mb-8">
+    <h1 class="text-4xl font-newsreader font-semibold mb-4 leading-tight">
+      {{ .Title }}
+    </h1>
+    <div class="text-gray-600 flex gap-4 flex-wrap">
+      {{ if .Date }}
+      <time datetime="{{ .Date.Format "2006-01-02" }}">
+        {{ .Date.Format "January 2, 2006" }}
+      </time>
+      {{ end }}
+      {{ with .Params.author }}
+      <span>{{ . }}</span>
+      {{ end }}
+      {{ if .ReadingTime }}
+      <span>{{ .ReadingTime }} min read</span>
+      {{ end }}
+    </div>
+  </header>
+
+  {{ if .Params.toc | default true }}
+  <aside class="mb-8 p-4 bg-gray-50 rounded">
+    <h2 class="text-sm font-semibold uppercase tracking-wide mb-3">{{ i18n "table_of_contents" | default "Table of Contents" }}</h2>
+    {{ .TableOfContents }}
+  </aside>
+  {{ end }}
+
+  <div class="font-newsreader text-lg leading-relaxed prose prose-newsreader">
+    {{ .Content }}
+  </div>
+
+  {{ with .Params.tags }}
+  <footer class="mt-12 pt-8 border-t">
+    <div class="text-sm">
+      <span class="font-semibold">{{ i18n "tags" | default "Tags" }}:</span>
+      {{ range . }}
+      <a href="{{ "/tags/" | relLangURL }}{{ . | urlize }}" class="inline-block mr-2 text-ifk-accent hover:text-ifk-accent-hover">
+        #{{ . }}
+      </a>
+      {{ end }}
+    </div>
+  </footer>
+  {{ end }}
+</article>
+
+{{ if or .NextInSection .PrevInSection }}
+<nav class="max-w-2xl mx-auto px-4 py-12 flex justify-between gap-4">
+  {{ with .PrevInSection }}
+  <a href="{{ .Permalink }}" class="flex-1 p-4 border rounded hover:bg-gray-50 text-left">
+    <div class="text-xs font-semibold uppercase text-gray-600">← {{ i18n "previous" | default "Previous" }}</div>
+    <div class="font-newsreader text-lg">{{ .Title }}</div>
+  </a>
+  {{ end }}
+  {{ with .NextInSection }}
+  <a href="{{ .Permalink }}" class="flex-1 p-4 border rounded hover:bg-gray-50 text-right">
+    <div class="text-xs font-semibold uppercase text-gray-600">{{ i18n "next" | default "Next" }} →</div>
+    <div class="font-newsreader text-lg">{{ .Title }}</div>
+  </a>
+  {{ end }}
+</nav>
+{{ end }}
+{{ end }}