It wasn't immediately clear the list ID needs to be populated in the HelloWorldAdaptiveCardExtension.manifest.json file, I did get an error if the items are not returned.
When adding IListItem - perhaps a note to say this will be defined later in the instructions.
In section: https://github.com/microsoft/Viva-Connections-Extensibility-Private-Beta/wiki/Lab-2:-Advanced-Card-View-Functionality#42---previous--next-buttons
When adding the last block of code, the IActionArguments needs to be added to the import statement.
Found couple of points
Other than that all working 😍