Docs: Document WP_Http_Cookie properties as nullable

[rejaulalomkhan]

Description

In WP_Http_Cookie, the $name and $value properties are initialized to null before the constructor sets them. When $data is passed as an associative array without a name key, the constructor returns early, leaving them uninitialized/null. Documenting both as string|null accurately reflects their lifecycle and satisfies PHPStan.

This resolves the sole error in the booleanOr.alwaysFalse baseline, retiring it, and removes two entries from the isset.property baseline.

Follow-up to [63899], [64222].
Trac ticket: https://core.trac.wordpress.org/ticket/65817

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[huzaifaalmesbah]

Thanks for working on this, @rejaulalomkhan!

It looks like this overlaps with #13983, which was opened a few days earlier for the same booleanOr.alwaysFalse baseline. That one also documents $domain as nullable and adds unit tests for the constructor's early return.

To avoid splitting review effort, would you be open to closing this in favour of #13983? A review there would be very welcome.

AI Review: Opus 5.5

[rejaulalomkhan]

Thanks @huzaifaalmesbah. #13983 covers the same baseline, also documents $domain as nullable, and adds tests for the constructor’s early return, so it’s the more complete fix. Closing in favour of #13983