Co-authored-by: Matthew Hodgson <[email protected]>

As @t3chguy mentions, we can't reduce the RTT on this
as the server will have forgotten sticky request params.

- Ensure `pos` is always a string
- Rename `rooms` to `ranges`
- Remove idempotency notes on `pos`
- Minor clarifications

- Clarify sort order ASC/DESC.
- Indenting on examples
- Document proposals for custom state key filters like LAZY and $current
- Document `limited`
- Document `timeout`

Sync v3 is technically the current sync in v1.1 of the Matrix Specification, so rename it for clarity.

- Add `is_dm` to the room response JSON if the room is a DM room.
- Add `invite_state` to the room response JSON if the room is an invite.
- Add `prev_batch` to the room response JSON for fetching scrollback via `/messages`.
- Add account data extension implementation

- Moves lists to the top-level, which makes sense given ops and room response JSON
  is list-scoped. Also at the top-level is room_subscriptions which has its own
  room response JSON, but no lists at all.
- Moves count to be list scoped (rather than the weird index matching you need to do today with counts)
- Replaces ops[].rooms with room ID rather than the room response JSON.
  This adds a bit of needless extra bandwidth but we need these to serve as pointers into..
- Add lists[].rooms which contains the room response JSON for that list.

We previously needed this command because room
data HAD to exist inside an `op`, so if a room
was updated without changing position then it
needed a command to say "don't change its position"
which _is_ the UPDATE command. Now that room data
sits outside the `ops`, we no longer need the
UPDATE command at all.

Reduces data duplication.

…s key omission

…ents

…y_notification_level

…el algo

Co-authored-by: Travis Ralston <[email protected]>

This makes goland happier.

Probably supported, becuase it's part of
    https://github.com/github/linguist/blob/master/lib/linguist/languages.yml#L3143-L3152

which is mentioned by
    https://docs.github.com/en/get-started/writing-on-github/working-with-advanced-formatting/creating-and-highlighting-code-blocks#syntax-highlighting

so that e.g. profile changes don't reorder the list

Much easier to implement like this, and might be good enough for now.

Co-authored-by: Richard van der Hoff <[email protected]>

Co-authored-by: Kévin Commaille <[email protected]>

Co-authored-by: Benjamin Bouvier <[email protected]>

This allows concurrent connections to a SS server.