"Raised hand" state not working properly in the sidebar with multiple sessions

[nickvergessen]

Steps to reproduce

1. Join a conversation with 2 sessions
2. In the session with the lower id raise hand

Expected behaviour

Sidebar shows you raise your hand

Actual behaviour

Sidebar doesn't show you raise your hand

[PVince81]

When I tested it worked fine with internal signaling, but not with the HPB.
It was likely related to the way session ids are mapped.

[nickvergessen]

yeah it is

[PVince81]

I did some quick debugging and it looks like it's going to be tricky.
The results of the participant list only contain one session id (likely the one from the aggregated "max" participant result).

Maybe we should adjust the participant API and make 'sessionId` an array ? Or for compatibility, add a new separate array that contains a list of known session ids for that participant.

[nickvergessen]

there is no compatibility needed atm as v4 is brand new

[PVince81]

for now I'll go with an extra property as I'm a bit afraid of all the code paths to touch that could potentially break in our frontend.
most code paths only need to know if the session is "0" or not

[PVince81]

PR here: #5482

I was able to remove the "sessionId" attribute still as the affected frontend code was minimal.