addRoot method
Add a root to the client's local list. Server is notified via
notifications/roots/list_changed.
Implementation
void addRoot(Root root) {
if (_roots.any((r) => r.uri == root.uri)) {
throw McpError('Root with URI "${root.uri}" already exists');
}
_roots.add(root);
if (isConnected) {
_sendNotification('notifications/roots/list_changed', {});
}
}