* feat(lobby): lobby chat

lobby chat support
knocking participants list updates
knocking participants conditonal checks to show message button
handle lobby chat message events
lobby messages from or to moderators only

Co-authored-by: Fecri Kaan Ulubey <f.kaan93@gmail.com>

* squash: Drop typos.

Co-authored-by: Kusi Musah Hussein <kusimusah@gmail.com>
Co-authored-by: Fecri Kaan Ulubey <f.kaan93@gmail.com>
Co-authored-by: Дамян Минков <damencho@jitsi.org>

Introduce navigation for all in-conference screens.