* docs: explain schedule state values
GET /v1/client/allocation/:alloc_id/pause?task=:task_name is a tiny but
critical API for observability of tasks with a schedule. This PR
explains each of the values which might be returned.
* correct docstring
* add missing state and expand PUT docs
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Co-authored-by: Aimee Ukasick <aimee.ukasick@hashicorp.com>