fix(sdk): keep isLoading true across interrupt→running hydration (#2703)

After a HITL interrupt is answered, replaying `interrupted` → `running`
on hydrate could leave `useStream().isLoading` stuck `false`: the
deferred interrupt reset fired after the later `running` and stomped it.
Deferred terminal resets now skip clearing when a newer `running` seq
has already been seen.


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Fixes # (issue)