switchboard 0.22.0

Changed

• Settings is tabbed, and the × never scrolls away. The one long scroll is now four groups — Profile, Appearance, New rooms and Sign-in & security (the password and passkeys, on a hosted broker or when you sign in with one) — in a rail of tabs on a desktop, with the arrow keys moving between them and Sign out at the foot of the rail. The × stays in a header that never scrolls, however far a group's own panel scrolls (#212). On a phone the groups show as a list with a one-line summary each; tapping one opens its own page, with ‹ Settings to go back. Saving still works exactly as it did before: every Save button, the theme and text-size buttons, and the password and passkey controls are unchanged, and a one-save-bar-per-group follows in a later pull request.
• The Add a machine card installs the latest release. Its first command is uv tool install switchboard-chat, without the broker's version pinned on. A machine and the broker only need to speak the same link protocol, and every release so far does. If a future release changes it, the broker refuses that machine and says to install the broker's version there.