Beitragsnavigation als Baustein (Dokumentschema v18)

Umut: "Beitragsseite gefaellt mir nicht, sollte wie bei kant-it.de sein
oder besser. Falls noetig Plugin bauen."

Die Originalseite hat Galerie, Vor/Zurueck zwischen Projekten und einen
Abschlussaufruf. Galerie und Aufruf gab es laengst - sie waren nur nicht
benutzt. Die Navigation gab es nicht.

Kein Plugin: ein Plugin ist hier ein Bausteintyp, dessen Eigenschaften der
Kern aufbewahrt, aber nicht rendert - es koennte also nichts ausgeben,
solange es keine Laufzeit dafuer gibt. Und die Nachbarn eines Beitrags
stehen in derselben Tabelle wie die Beitragsliste, die der Kern schon
fuellt. Also ein Baustein: postnav.

Gespeichert sind zwei Beschriftungen, mehr nicht - welcher Beitrag vorher
und nachher kommt, entscheidet der Renderer. Gesucht wird innerhalb
derselben Kategorie, und am Rand wird nicht umgebrochen.

Ausserdem: die uebernommenen Projekttexte begannen mit dem wiederholten
Titel (20 Beitraege), und schmale Abschnitte standen links statt mittig -
max-width ohne margin:auto ist eine halbe Einstellung.

Geprueft: 396 Tests unter PHP 8.2 und 8.4, 18 JS-Tests, Editortest,
Browserpruefung, axe ohne Verstoss auf der Beitragsseite.

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

templates/blocks/block.html.twig

@@ -10,7 +10,7 @@
     {% set tag = type == 'section' ? 'section' : 'div' %}
     <{{ tag }} id="{{ block.id }}" class="block-{{ type }} tone-{{ layout.tone|default('paper') }} width-{{ layout.width|default('normal') }}{{ designClasses }}">
         {% if type == 'section' %}<div class="shell section-inner">{% endif %}
-        {% for child in block.children|default([]) %}{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), eagerImage: eagerImage|default(null)} only %}{% endfor %}
+        {% for child in block.children|default([]) %}{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), neighbours: neighbours|default({}), eagerImage: eagerImage|default(null)} only %}{% endfor %}
         {% if type == 'section' %}</div>{% endif %}
     </{{ tag }}>
 {% elseif type == 'heading' %}
@@ -45,7 +45,7 @@
     </figure>
 {% elseif type == 'logos' %}
     <ul id="{{ block.id }}" class="block-logos{{ designClasses }}">
-        {% for child in block.children|default([]) %}<li>{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), eagerImage: eagerImage|default(null)} only %}</li>{% endfor %}
+        {% for child in block.children|default([]) %}<li>{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), neighbours: neighbours|default({}), eagerImage: eagerImage|default(null)} only %}</li>{% endfor %}
     </ul>
 {% elseif type == 'cta' %}
     <div id="{{ block.id }}" class="block-cta{{ designClasses }}">
@@ -88,7 +88,7 @@
     {% set section = sections[props.partial]|default(null) %}
     {% if section %}
         <div id="{{ block.id }}" class="block-partialref{{ designClasses }}">
-            {% for child in section.blocks %}{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), eagerImage: eagerImage|default(null)} only %}{% endfor %}
+            {% for child in section.blocks %}{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), neighbours: neighbours|default({}), eagerImage: eagerImage|default(null)} only %}{% endfor %}
         </div>
     {% elseif editing|default(false) %}
         <p id="{{ block.id }}" class="block-unavailable" role="note">Die verknüpfte Sektion „{{ props.partial }}“ gibt es nicht mehr. Der Verweis bleibt gespeichert.</p>
@@ -117,22 +117,22 @@
         <ul class="tabs-nav">
             {% for child in block.children|default([]) %}<li><a href="#{{ child.id }}">{{ child.props.title }}</a></li>{% endfor %}
         </ul>
-        {% for child in block.children|default([]) %}{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), eagerImage: eagerImage|default(null)} only %}{% endfor %}
+        {% for child in block.children|default([]) %}{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), neighbours: neighbours|default({}), eagerImage: eagerImage|default(null)} only %}{% endfor %}
     </div>
 {% elseif type == 'tabitem' %}
     <section id="{{ block.id }}" class="block-tabitem{{ designClasses }}">
         <h3 class="tabs-heading">{{ props.title }}</h3>
-        {% for child in block.children|default([]) %}{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), eagerImage: eagerImage|default(null)} only %}{% endfor %}
+        {% for child in block.children|default([]) %}{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), neighbours: neighbours|default({}), eagerImage: eagerImage|default(null)} only %}{% endfor %}
     </section>
 {% elseif type == 'accordion' %}
     <div id="{{ block.id }}" class="block-accordion{{ designClasses }}">
-        {% for child in block.children|default([]) %}{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), eagerImage: eagerImage|default(null)} only %}{% endfor %}
+        {% for child in block.children|default([]) %}{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), neighbours: neighbours|default({}), eagerImage: eagerImage|default(null)} only %}{% endfor %}
     </div>
 {% elseif type == 'accordionitem' %}
     <details id="{{ block.id }}" class="block-accordionitem{{ designClasses }}"{% if props.open|default(false) %} open{% endif %}>
         <summary>{{ props.title }}</summary>
         <div class="accordion-body">
-            {% for child in block.children|default([]) %}{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), eagerImage: eagerImage|default(null)} only %}{% endfor %}
+            {% for child in block.children|default([]) %}{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), neighbours: neighbours|default({}), eagerImage: eagerImage|default(null)} only %}{% endfor %}
         </div>
     </details>
 {% elseif type == 'icon' %}
@@ -161,7 +161,7 @@
     <div id="{{ block.id }}" class="block-slider{{ designClasses }} slide-desktop-{{ props.desktopVisible }} slide-tablet-{{ props.tabletVisible }} slide-mobile-{{ props.mobileVisible }}{{ props.snap ? ' slider-snap' : '' }}{{ props.dots ?? false ? ' slider-dots' : '' }}"{% if props.autoplay|default(0) >= 3 %} data-autoplay="{{ props.autoplay }}"{% endif %}
          tabindex="0" role="group" aria-label="Zum Blättern seitwärts scrollen">
         {% for child in block.children|default([]) %}
-        <div class="slider-slide">{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), eagerImage: eagerImage|default(null)} only %}</div>
+        <div class="slider-slide">{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), neighbours: neighbours|default({}), eagerImage: eagerImage|default(null)} only %}</div>
         {% endfor %}
     </div>
 {% elseif type == 'embed' %}
@@ -198,9 +198,13 @@
         {% set feed = postLists[block.id]|default([]) %}
         {% include 'blocks/post-list.html.twig' with {posts: feed.posts|default(feed), pages: feed.pages|default(1), page: feed.page|default(1), total: feed.total|default(null), showMeta: block.props.showMeta ?? true, showExcerpt: block.props.showExcerpt ?? true, showTerms: block.props.showTerms ?? true} only %}
     </div>
+{% elseif type == 'postnav' %}
+    <div id="{{ block.id }}" class="block-postnav{{ designClasses }}">
+        {% include 'blocks/post-nav.html.twig' with {previous: neighbours.previous|default(null), next: neighbours.next|default(null), previousLabel: props.previousLabel|default('Vorheriger Beitrag'), nextLabel: props.nextLabel|default('Nächster Beitrag')} only %}
+    </div>
 {% elseif type == 'gallery' %}
     <div id="{{ block.id }}" class="block-gallery{{ designClasses }}" role="group" aria-label="Bildergalerie">
-        {% for child in block.children|default([]) %}{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), eagerImage: eagerImage|default(null)} only %}{% endfor %}
+        {% for child in block.children|default([]) %}{% include 'blocks/block.html.twig' with {block: child, editing: editing|default(false), postLists: postLists|default({}), forms: forms|default({}), breadcrumbs: breadcrumbs|default([]), navigation: navigation|default({}), sections: sections|default({}), richText: richText|default(false), richHeadings: richHeadings|default(false), neighbours: neighbours|default({}), eagerImage: eagerImage|default(null)} only %}{% endfor %}
     </div>
 {% else %}
     {#