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>

src/Content/DocumentValidator.php

@@ -13,7 +13,7 @@ final class DocumentValidator
     /** Blocks introduced with schema v6 for the sections a marketing page actually needs. */
     public const V6_TYPES = ['iconcard', 'stat', 'quote', 'logos', 'cta', 'contact', 'divider', 'spacer', 'accordion', 'accordionitem'];
     /** Icons ship as inline SVG from this fixed list; no icon font and no external request. */
-    public const ICONS = ['app', 'web', 'design', 'network', 'hardware', 'shop', 'support', 'shield', 'clock', 'star', 'phone', 'mail', 'pin', 'check'];
+    public const ICONS = ['app', 'web', 'design', 'network', 'hardware', 'shop', 'support', 'shield', 'clock', 'star', 'phone', 'mail', 'pin', 'check', 'people', 'music', 'home'];
     public const SPACER_SIZES = ['small', 'medium', 'large', 'huge'];
     /** Schema v7: tabs, the one pattern that needs a script to become a real widget. */
     public const V7_TYPES = ['tabs', 'tabitem'];
@@ -265,6 +265,11 @@ final class DocumentValidator
             if (array_key_exists('collapse', $props)) {
                 $this->require($schemaVersion >= 22 && in_array($props['collapse'], ['tablet', 'mobile', 'never'], true), 'Unbekannte Hamburger-Umschaltung oder Dokumentschema vor v22.');
             }
+            if (array_key_exists('burgerLabel', $props)) {
+                // Wie der Knopf beschriftet ist. „Nur Symbol“ behält den Text für Vorlesesoftware:
+                // ein Knopf ohne Namen ist für sie ein Knopf ohne Zweck.
+                $this->require(in_array($props['burgerLabel'], ['both', 'text', 'icon'], true), 'Für den Menü-Knopf sind „both", „text" und „icon" vorgesehen.');
+            }
             if (isset($props['layout'])) {
                 $this->require($schemaVersion >= 16, 'Die Menüart braucht Schema v16.');
                 $this->require(in_array($props['layout'], ['horizontal', 'vertical', 'burger'], true), 'Unbekannte Menüart.');