Since #2849 there is no limit for the current state we fetch to
calculate history visibility. In large rooms this can cause us to fetch
thousands of membership events we don't really care about.
This now only gets the state event types and senders in our timeline,
which should significantly reduce the amount of events we fetch from the
database.
Also removes `MaxTopologicalPosition`, as it is an unnecessary DB call,
given we use the result in `topological_position < $1` calls.
This makes the following changes:
- get state deltas without the user supplied filter, so we can actually
"calculate" state transitions
- closes `stmt` when using SQLite
- Adds presence for users who newly joined a room, even if the syncing
user already knows about the presence status (should fix
https://github.com/matrix-org/complement/pull/516)
Improves the control flow of `GetStateDeltas` for clarity and possibly
also fixes a bug where duplicate state delta entries could be inserted
with different memberships instead of being correctly overridden by
`join`.
This now uses a transaction per stream, so that errors in one stream
don't propagate to another, and we therefore no longer need to do hacks
to reopen a new transaction after aborting a failed one.
This should transactional snapshot isolation for `/sync` etc requests.
For now we don't use repeatable read due to some odd test failures with
invites.
