You could submit an issue or a pull request to update the csv file at https://github.com/FederatedMethods/packages/blob/main/package_list.csv. Most of this information is gathered from the package info on GitHub or the CRAN, so you may need to update the information there, then it will appear here tomorrow.
Some packages are retired but still available for use. We list them here for reference, but they are not actively maintained. If you have questions about a retired package, please contact the maintainers directly. Or, if you want to help maintain a retired package, please reach out to the maintainers to discuss how you can contribute.
Yes, it is. There is some redundancy, as e.g. most client side packages have a corresponding server side package, but sometimes there are multiple server side packages for one client side function. There are also some packages which just work on the server side. Here we list everything for completeness.