After reading your comment, I was interested in whether or not I could achieve this through the built-in Shortcuts app. Unfortunately, "Restart" is not an available action.
Edit: Actually, I was looking in the wrong place. It’s an option for the "Shut Down” action. Thanks, @jwond!
Thank you very much. I've wanted to have a weekly reboot of my phone for years now, and it drove me nuts that I couldn't create a shortcuts automation for it.
Just tried it. Unfortunately, even when you choose "Run Immediately", it still asks for user input when the time comes ("Are you sure you want to restart this iPhone?")