function is_custom_element_node(node) {
	return (
		node.type === 'RegularElement' &&
		(node.name.includes('-') ||
			node.attributes.some((attr) => attr.type === 'Attribute' && attr.name === 'is'))
	);
}
@param {AST.RegularElement | AST.SvelteElement} node
@returns {boolean}