Sort is no longer configurable and we always sort rooms by the `stream_ordering` of the last event in the room or the point where the user can see up to in cases of leave/ban/invite/knock.
PR where this was introduced: https://github.com/matrix-org/synapse/pull/14817
### What does this affect?
`get_last_event_in_room_before_stream_ordering(...)` is used in Sync v2 in a lot of different state calculations.
`get_last_event_in_room_before_stream_ordering(...)` is also used in `/rooms/{roomId}/members`
During the migration the automated script to update the copyright
headers accidentally got rid of some of the existing copyright lines.
Reinstate them.
There are a bunch of places we call get_success on an immediate value, which is unnecessary. Let's rip them out, and remove the redundant functionality in get_success and friends.
The unstable identifiers are still supported if the experimental configuration
flag is enabled. The unstable identifiers will be removed in a future release.
SYN-287
This requires that HS owners either opt in or out of stats reporting.
When --generate-config is passed, --report-stats must be specified
If an already-generated config is used, and doesn't have the
report_stats key, it is requested to be set.
