Implement https://github.com/vector-im/element-web/issues/18957 following requirements:
* Create a new right panel view to list all the threads in a given room.
* Change ThreadView previous phase to be ThreadPanel rather than RoomSummary
* Implement local filters for My and All threads
In addition:
* Create a new TileShape for proper rendering requirements (hiding typing indicator)
* Create new timelineRenderingType for proper rendering requirements
We're anticipating development of polls soon, so for efficiency reasons we're getting the labs flag in early. If something goes wrong with the plan, this whole change will be reverted.
Also hide video mute button on voice calls (awaiting clarification from design)
and fix mute keyboard shortcuts by moving them out of roomview & into
callview.
This removes all images we no longer reference in the app. This should be safe,
as Webpack only adds images to the build output if they are referenced.
