Mix screenshare audio with mics again to avoid playback autoplay problems in iOS, fixed desync with aresample

use libopus decoder and encoder, its better than built-in ffmpeg/flac
don't mix screenshare audio with mics, was generating desync with bad audio segments, encode it together with video file (TODO: needs adjustments in playback)

Recording processing using MP4/OGG temporary files, stream copy, and customizable (lower) frame rates.
Discussion from https://github.com/bigbluebutton/bigbluebutton/issues/2483

When managing Etherpad's pads, Meteor makes API calls to initiate the closed captions
and shared notes modules. The pad id was being mapped to a shorter id than the meeting
id because of a Etherpad lenght limitation.

Changed to something less guessable.

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.10.8 to 1.11.0.
- [Release notes](https://github.com/sparklemotion/nokogiri/releases)
- [Changelog](https://github.com/sparklemotion/nokogiri/blob/main/CHANGELOG.md)
- [Commits](https://github.com/sparklemotion/nokogiri/compare/v1.10.8...v1.11.0

)

Signed-off-by: dependabot[bot] <support@github.com>

Fix file existence test.

PR #9857 was incomplete and did not completely fix the issues described in #9062 and #9110 (dublicate).

Collects the shared notes' HTML raw data and publishes it along with the other
recording files. The playback will fetch for this file and include an option to
display it's content over the chat.

Not sure what causes this issue, but there's nothing reasonable that can
be done to draw a shape with no thickness. Just skip it.

The indexes returned in recording events from BBB refer to positions
within a UTF-16 encoded string. Rather than attempt to untangle this in
the server (which might have a performance cost), it's easier to switch
the caption processing code to operate in UTF-16 encoding as well to
make it work consistently.

The PyICU library provides a UnicodeString type which is a UTF-16 string
similar to Java and JavaScript, but which supports all the python
indexing methods. It's fairly straightforwards to swap it in in place of
the types used previously, and works natively as an input to the ICU
line break iterator too.

Fixes #10531

The previous implementation of the BigBlueButton.execute method runs the
process with separate stdout and stderr streams. It first reads all of
the output from stdout, then reads all of the output from stderr.

This can cause a deadlock if the process writes a lot of data to stderr.
The IO buffer for stderr could fill, blocking progress. But since it
hasn't closed stdout, the ruby script is still waiting on a read to
stdout.

Switch to an execution method (using IO.popen) that allows combining
stdout and stderr into a single stream, eliminating the issue.

probably a simple typo

On my server 2.3 alpha, the method metadata_for(meeting_id) gives back {}
(empty Hash). Thus "return if meeting_metadata.nil?" does not occur.

Does @redis.hgetall give {} instead of nil, even though there is a comment in
node_modules/redis/lib/utils.js "hgetall converts its replies to an Object. If
the reply is empty, null is returned"???

On my server 2.3 alpha, the method metadata_for(meeting_id) gives back {}
(empty Hash). Thus "return if meeting_metadata.nil?" does not occur.

Does @redis.hgetall give {} instead of nil, even though there is a comment in
node_modules/redis/lib/utils.js "hgetall converts its replies to an Object. If
the reply is empty, null is returned"???

Update the list of invalid characters based on what the XML
specification permits and discourages.

Use the ruby string `scrub` method to remove invalid characters that
can't be expressed in the `tr` syntax, like unpaired surrogates and
UTF-8 prefix bytes.

* added post_events example and analytics callback

* updated dependency

Bumps [rack](https://github.com/rack/rack) from 2.1.1 to 2.2.3.
- [Release notes](https://github.com/rack/rack/releases)
- [Changelog](https://github.com/rack/rack/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rack/rack/compare/2.1.1...2.2.3

)

Signed-off-by: dependabot[bot] <support@github.com>

This commit fixes an issue with reading and writing files.
File.open is used which means that a file will remain open
unless explicilty closed or the program exit. This doesn't work
for an NFS mount as the scripts try to "rm -rf" when the file
is still open. This commit fixes that by replacing all .opens
with .reads

Playback a presentation does not start on iPad with iPadOS 13 and higher.
The root cause is that `mobileAndTabletCheck` does not detect an iPad as mobile device.
The reasons for this are discussed here:  https://github.com/serbanghita/Mobile-Detect/issues/795
A way to detect Safari on IPadOS as mobile device is described here: https://stackoverflow.com/a/60553965
I've added a function `detectLyingiOS13iPad` to work around this problem.