First pass at the new video tile designs

Here, I've begun updating the styles of video tiles to match the new designs. Not yet updated: the local volume option is supposed to go inside an overflow menu now, but I haven't gotten to that yet.

To make the outlines on hovered / speaking tiles show up properly, I have to remove the usePageFocusStyle hack, which was preventing CSS outlines from being used for anything other than focus rings. I honestly can't tell what problem it was solving in the first place: focus rings still appear to behave as expected throughout the application.

src/App.tsx

@@ -25,7 +25,6 @@ import { LoginPage } from "./auth/LoginPage";
 import { RegisterPage } from "./auth/RegisterPage";
 import { RoomPage } from "./room/RoomPage";
 import { ClientProvider } from "./ClientContext";
-import { usePageFocusStyle } from "./usePageFocusStyle";
 import { SequenceDiagramViewerPage } from "./SequenceDiagramViewerPage";
 import { InspectorContextProvider } from "./room/GroupCallInspector";
 import { CrashView, LoadingView } from "./FullScreenView";
@@ -48,8 +47,6 @@ export default function App({ history }: AppProps) {
     });
   });
 
-  usePageFocusStyle();
-
   const errorPage = <CrashView />;
 
   return (