Add three icons, a styleable menu button and a reliable back-to-top in 1.13.0

The icon set had no drawing for people, music or a house - the three pictures
the Tagespflege Moldovan template asks for. They join as `people`, `music` and
`home`; a test keeps the list and the drawings together, because a missing path
renders an empty `<path d="">`: invisible, without an error.

An icon block's own colour never reached its drawing: the embedded SVG carries
the same `block-icon` class as its wrapper and set the accent colour again.
`.block-icon .block-icon{color:inherit}` fixes it at the root.

The menu button becomes a thing you can shape. `burgerLabel` chooses symbol and
text, text only or symbol only (which keeps the name for screen readers), and
the new style group `menu` targets the button itself, the way `img` targets an
image and `controls` the slider. Inside the header the opened menu now lies
under the header across the full width instead of pushing the header apart -
on a phone that looked like a missing navigation.

The back-to-top button no longer depends on `animation-timeline: scroll()`. A
browser that parses the property but does not run the timeline left it in the
first frame of the animation: permanently invisible. Two classes from
scrolled.js decide now, and without a script the button simply stays visible.

Also: the Tagespflege Moldovan rebuild as its own installation, built only by
`scripts/seed-tagespflege-moldovan.php`.

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

templates/blocks/block.html.twig

@@ -99,7 +99,9 @@
          aria-label="{{ {header: 'Hauptnavigation', secondary: 'Zweite Navigation', footer: 'Fußzeile', legal: 'Rechtliches'}[props.slot]|default('Navigation') }}">
         {% if menuLayout == 'burger' or collapse != 'never' %}
         <details class="menu-burger">
-            <summary><span class="burger-lines" aria-hidden="true"></span><span class="burger-text">Menü</span></summary>
+            {# Nur Symbol behält den Namen für Vorlesesoftware; sichtbar ist dann nur der Strich. #}
+            {% set burger = props.burgerLabel|default('both') %}
+            <summary>{% if burger != 'text' %}<span class="burger-lines" aria-hidden="true"></span>{% endif %}<span class="burger-text{{ burger == 'icon' ? ' visually-hidden' : '' }}">Menü</span></summary>
             <div class="menu-burger-body">{% include 'nav.html.twig' with {links: links} only %}</div>
         </details>
         {% endif %}