Disable WYSIWYG editing of macros that require content nesting

Currently, XWiki macros can't be properly implemented in Cristal. WYSIWYG edition for these should be disabled to still allow displaying them in the editor (as read-only) and to avoid losing block informations when saving. Specifically, macros that should be set as read-only in the editor are:

• XWiki block macros (as they can take blocks as content, instead of only inline contents as allowed by BlockNote)
• XWiki inline macros (as they can take inline contents as content, instead of only text as allowed by BlockNote)