* Return task with NULL result instead of NULL
* move Task.FromResult call out of lock
* Update ReleaseNotes.md
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Co-authored-by: Christian <6939810+chkr1011@users.noreply.github.com>
* Fix timestamp check in server keep-alive monitor
* Retain the original client statistics property name
- add comments to clarify meaning
- add separate public "received" timestamp property
* fix comment
* Set IsSessionPresent in CONNACK if client session exists
* Set IsSessionPresent in CONNACK if client session exists;
- restore white space differences to make comparison easier