Improve the locking / unlocking accessibility when using screen readers

[marvellousmachine]

1. Currently it is not possible to lock / unlock server from the main screen when using a screen reader. You could either make it a HTML button as planned, or use the ARIA role button. When you go for the HTML button version, I suggest you would make the label dynamic: "Lock server" when unlocked and "Unlock server" when locked.
2. Also it would be helpful if the window title would change in locked state by prepending something like 🔒 or 🔑. For example: "🔒 FM-DX Webserver [Server Name]"

[NoobishSVK]

1. I have added an aria-label (which will be available with the next update).
2. The icons are already available, but were missing aria-labels, I have added them.

[marvellousmachine]

Could you also please add the button role for both admin lock and password lock and make them focusable when tabbing?
Also there is a typo: "ock Tuner (Admin)