Add INCREX keyspace notification event

[sundb]

Note

Low Risk
Low risk: documentation-only change that adds INCREX to the keyspace notification event list with no runtime or behavioral impact.

Overview
Documents keyspace notification behavior for the INCREX command, including which incrby/incrbyfloat event is emitted and how expiration-related options (EX/PX/EXAT/PXAT/PERSIST) map to additional expire/persist/del events.

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[CLAassistant]

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[dwdougherty]

Hi @sundb. Please change the target of the PR to DOC-6334 (my 8.8 feature branch). It can't go to main.

Apart from that, LGTM and I'll approve and merge when the target is changed.

[dwdougherty]

If it's easier for you, I can cherry-pick your change and add it to my other INCREX ticket. I'll leave it up to you.

[sundb]

If it's easier for you, I can cherry-pick your change and add it to my other INCREX ticket. I'll leave it up to you.

sure. thx for your help.