Migrate WordPress site to Hugo

Replaces the WordPress 7.0.2 / HitMag site with a static Hugo build,
deployed by Gitea Actions over rsync/SSH.

Content: 26 files (9 pages + 17 posts) as Markdown page bundles, plus
127 of 165 media attachments. The remaining 38 are media-library
leftovers that appear nowhere on the live site; they are listed in
MIGRATION.md.

The WXR export contains neither media binaries nor widgets, so both were
recovered from the live host before it is retired:
  - tools/fetch_media.py downloads all uploads, capping them at 2000px
  - tools/build_data.py scrapes the "Unsere Mitglieder" and
    "In Erinnerung" widgets into data/*.yaml

TablePress' six Termine tables became data/termine.yaml, rendered with
the newest year expanded and earlier years collapsed. Old permalinks are
not preserved (clean slugs, no redirects, as agreed).

Custom layouts, no third-party theme. Plain CSS, since the pinned Hugo
0.164.0 is the non-extended build and cannot compile Sass.

Verified: clean build with zero warnings, 718 internal links checked and
none broken, no surviving wp-content URLs.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

layouts/_markup/render-image.html

@@ -0,0 +1,18 @@
+{{- /* Markdown images inside a page bundle get resized and lazy-loaded.
+       External or non-resource images are passed through unchanged. */ -}}
+{{- $src := .Destination -}}
+{{- $alt := .Text | plainify -}}
+{{- $caption := .Title -}}
+{{- with .Page.Resources.GetMatch $src -}}
+  {{- $img := . -}}
+  {{- if gt .Width 1200 -}}{{- $img = .Resize "1200x webp q82" -}}{{- end -}}
+  <figure class="content-figure">
+    <a href="{{ .RelPermalink }}">
+      <img src="{{ $img.RelPermalink }}" width="{{ $img.Width }}" height="{{ $img.Height }}"
+           alt="{{ $alt }}" loading="lazy" decoding="async">
+    </a>
+    {{- with $caption }}<figcaption>{{ . }}</figcaption>{{ end -}}
+  </figure>
+{{- else -}}
+  <img src="{{ $src | safeURL }}" alt="{{ $alt }}" loading="lazy" decoding="async">
+{{- end -}}