The "Add a device" modal: pasting the tokened URL another machine's daemon prints saves that daemon as a device this browser can run sessions on — the token stays in this browser and never reaches a server, an optional name overrides the host, and a URL without a token cannot be saved because it could not authenticate.

## Before writing SPEC.md files

Read https://raw.githubusercontent.com/brillout/sdd/refs/heads/main/sdd.md
