Add an AFK "Lock" for Public Environments

My suggestion is essentially the post title. Add a way to "lock up" the discord app for when using Discord at work, cafe's, etc. and you have to step away for a moment.

Adding this feature would promote account safety and security by enabling a user to disallow access to their personal Discord account when they are not at the station. Currently, the only way to achieve the same effect is to either close Discord completely, log out of your account, or hope no one opens the app and peruses your information.

For design:

• the lock screen can have a notice stating it's in a "locked/AFK state",
• display an option allowing the user to "unlock" the app by entering the used accounts credentials/2FA,
• display an option allowing the user to logout,