Offer 98 icons in a dialog and style a button icon under Design

The icon set grows from 33 to 98 drawings in seven categories (arrows,
contact, commerce, files and media, people and security, house and trade,
general), including truck, cart, euro, camera, tools and solar. icons.js is
the single source; npm run build:icons writes the Twig drawings and the
validator list, and a test keeps them equal.

Choosing an icon no longer fills the panel with tiles: the panel shows the
current icon with "Change", which opens a modal with category tabs and named
tiles, keyboard navigable, closing with Escape. Button, icon and icon card
share it.

A new style group "Symbol" targets the icon inside a button per device and
on hover: colour, background, size, padding, radius, rotation, plus the gap
to the text. Schema v26 adds hover motion (slide, reveal) and an icon-only
button whose label stays as the accessible name and keeps the line height.
ADR 109.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

public/assets/editor-model.js

@@ -175,6 +175,7 @@ export function repairSchema(document) {
       if ('collapse' in props) upgradeDocument(document, 22);
       if ('faq' in props) upgradeDocument(document, 23);
       if (block.type === 'button' && ('icon' in props || 'iconPosition' in props)) upgradeDocument(document, 25);
+      if (block.type === 'button' && ('iconMotion' in props || 'iconOnly' in props)) upgradeDocument(document, 26);
       walk(block.children);
     }
   };
@@ -343,7 +344,7 @@ export const devices = { desktop: 'Desktop', tablet: 'Tablet', mobile: 'Mobil' }
 // blieb bei 12 stehen, während Bausteine schon v13 bis v15 verlangten: in einem aktuellen Dokument
 // liess sich dann gar nichts mehr einfügen, und ein Symbol, ein Slider oder ein externer Inhalt
 // nirgends. Eine Zahl, an einer Stelle.
-export const SCHEMA_VERSION = 25;
+export const SCHEMA_VERSION = 26;
 
 export const VISIBILITY = { all: 'Auf allen Geräten', desktop: 'Nur Desktop', tablet: 'Nur Tablet', mobile: 'Nur Mobil', 'hide-desktop': 'Auf Desktop ausblenden', 'hide-tablet': 'Auf Tablet ausblenden', 'hide-mobile': 'Auf Mobil ausblenden', hidden: 'Überall ausblenden' };
 
@@ -685,6 +686,7 @@ export function relevantProperty(block, key, property) {
   const container = isContainer(block);
   if (property.group === 'slider') return block.type === 'slider';
   if (property.group === 'menu') return block.type === 'menu';
+  if (property.group === 'icon') return block.type === 'button' && block.props?.icon !== 'none';
   if (property.group === 'image') return ['image', 'gallery', 'logos', 'postlist'].includes(block.type);
   if (property.group === 'text' || key === 'textShadow') return !['image', 'gallery', 'logos', 'spacer', 'divider', 'embed'].includes(block.type);
   if (key === 'columnWidths') return block.type === 'row';