Faster sign-in and sign-out, and other fixes

What was fixed:

• Signing out happens right away and no longer waits in the background.
• After signing out, the sign-in screen starts empty, without your address or password in the fields.
• A new account opens the app right away, and a new passkey no longer holds you up.
• "I already have an account" is a full button above "Get started".
• The notifications switch during sign-up now works and tells you why when notifications are blocked.
• The consent sheet shows the full text and one clear button.
• Settings > Version always lists the newest version.
• Chats > Archived fits the screen and looks like the chat list.