Fix legacy client with customHeartbeat:false

Add guest lobby messages

Update fsesl password on package installation

Fixes incomplete session data error caused by PR #11529

When a moderator ends a meeting, indicate to viewers who ended the meeting

on installation of akka-bbb-fsesl, update ESL password in /etc/bigbluebutton, where we're starting to
put the configuration stuff, instead of /usr/share/bbb-fsesl-akka/conf/application.conf

FreeSWITCH configuration file (event_socket.conf.xml) and add
FreeSWITCH as a package dependency to make sure that it gets
configured first

Moderators are able to send a message to the meeting's guest lobby. This new
event reaches bbb-web and is sent to the guest user with her/his status response
while polling. All guest users that are waiting for acceptance will be able to
read this message.

enableGuestLobbyMessage is disabled by default.

Improve the way we observe changes on Users's collection

It is safer to look at subscriptions's state to users instead of depending
on the initial state of the collection at mounting time. Although
i couldn't force any race conditions on this, there's a chance it could
happen. The fix avoid this problem.
This complements #11533

Changes on end meeting message

Fixes incorrectly displaying of 'restore presentation' button when presentation is disabled

Added text for override of bbb-web.properties

add overlay config for bbb-web

there was a call of grep which failed when the config file does not
exist yet. check existance of file first.

Move some validations to the User's collection query

Bbb core http endpoint wip

Also removed unnecessary fields

Improve performance when doing user join notifications

Co-authored-by: Anton Georgiev <antobinary@users.noreply.github.com>

Complements #11533

Replaces the PR #10604, which has been temporarily fixed a problem in 2.3a2, that is, the slide size gets crazy when turning on and off fullscreen mode. Since #10604 was just a workaround, I tried to fix it in a way making more sense.

### Closes Issue(s)

closes #10459 (already closed by #10604) and #10589

### Motivation

#10604 is fixing the problem by calling "slide change" event, although the slide has not been changed actually. I tried to fix the same problem by adding a "full screen change" event listener in the layout manager, which I think is more elegant.

Merge 2.2 into develop

Waiting users audio and push alerts

Fix openPanel errors related to polling and shared notes

Backport audio improvements from 2.3