Streams
The container for workable items inside a Runline.
A Stream is the container for the workable Items inside a Runline: the ones a Runner or a person actively moves through states, as opposed to Items that are only recorded.
What it is for
Not every Item is worked the same way. A Loan or an Alert moves through a lifecycle (new, in review, approved, closed); a logged Decision or a Thought is recorded but not itself worked. The Stream is the boundary between the two: it holds the Items that have a queue, a state, and an owner. When a Runner asks "what is on my plate," it is reading a Stream.
How it fits
A Runline can have more than one Stream, one per kind of work it manages. Each Stream is scoped to its Runline and its org, so one credit union's queues never bleed into another's. The Item type decides whether an Item is workable, and therefore whether it belongs on a Stream at all.