Threads - first iteration (#5165)
* Initial threads support: parse `ThreadSummary`.
Replace several `isThreaded` values with `EventThreadInfo`, which contains the info about the event either being the root of a thread or part of it.
* Add `Threaded` timeline mode
* Add a `liveTimeline` parameter to `TimelineController`'s constructor. This way we can customise which timeline will be used as the 'live' one. Also add `@LiveTimeline` DI qualifier for the actual live timeline of the room.
* Create `ThreadedMessagesNode`. Allow opening a thread in a separate screen.
* Add the callbacks for the list menu actions - even if they're the wrong ones and will send the data to the room instead
* Send attachments and location in threads
* Fix polls in threads, add support for sending voice messages in threads
* Display thread summaries only when the feature flag is enabled
* Use 'Reply' instead of 'Reply in thread' when in threaded timeline mode
* Remove incorrect usage of `Timeline` in `MessageComposerPresenter`. This led to replies to threaded events not appearing as actual replies.
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Co-authored-by: ElementBot <android@element.io>
