WPB-19927 sync marker not sent when opening multiple times the web socket

[battermann]

# this marker comes from the connection in the test that is only created to empty the queue
[[email protected]] sync_marker published ws_id=38493 marker_id="ce84a182-14ac-471a-985f-7b7b07e61b1a"
# probably the client-add event is acked here
[[email protected]] ack received ws_id=38493 delivery_tag=1 multiple=False
# sync marker is received...
[[email protected]] sync_marker received ws_id=38493 marker_id="ce84a182-14ac-471a-985f-7b7b07e61b1a" delivery_tag=2
# and acked
[[email protected]] ack received ws_id=38493 delivery_tag=2 multiple=False

# the following logs are the relevant ones:
# sync marker is published from the first connection
[[email protected]] sync_marker published ws_id=515828 marker_id="bf6b1c77-814c-4f71-82a8-cadd1194fa77"
# marker received but never acked (the connection was close on the client immediately)
[[email protected]] sync_marker received ws_id=515828 marker_id="bf6b1c77-814c-4f71-82a8-cadd1194fa77" delivery_tag=1
# sync marker is published from the second conncetion
[[email protected]] sync_marker published ws_id=670799 marker_id="0b7ce1fe-046d-4de5-82a8-b58742dc1747"
# but it is received by the consumer of the first connection (which is still within the window between killed on the client and channel being closed by the server), and even though not acked the message is not requeued soon enough to be consumed by the second connection
[[email protected]] sync_marker received ws_id=515828 marker_id="0b7ce1fe-046d-4de5-82a8-b58742dc1747" delivery_tag=2
----- Events.testSyncMarkerMissingAcrossConnections FAIL (3.93 s; failed at 2026-01-23T08:12:42.343Z) -----
assertion failure:
Expected sync marker not observed: 0b7ce1fe-046d-4de5-82a8-b58742dc1747

call stack:
1. assertFailure at test/Test/Events.hs:767
     unless (marker2 `elem` allMarkersReceived) $ assertFailure $ "Expected sync marker not observed: " <> marker2




Attempting to delete federation V0 queues...
Attempting to delete federation V1 queues...
----------
1 test run.

1 failed test:
 - Events.testSyncMarkerMissingAcrossConnections

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