CQ Xiao

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> Thanks for the PR! can you please also mention the changes in CHANGELOG as well? Updated.

Moved the code to apply broker returned session_expiry_interval here, please check.

IMHO we can use `VecDeque` to save `pkid/publish` and `NoticeTx`, the reasons: 1. Since the packets are always ordered, the `push_back` and `pop_front` can be used, they work faster than...