The seam: named readers, error classes, candidates, seven more shapes

The things consumers worked around are served. A consumer of the timeline names its own read pointer (reader), so two bots on one account stop moving each other's window and the 'anything new?' hint on every response finally means something for a bot that marks; and an empty window answers in a fraction of the time. Every error now says what kind of thing it is in one word (retry, input, subject, server, budget), so a pending live read is no longer counted as a failure. An agent that passes the asker's display name gets the matching clan members back in the refusal instead of pulling the roster to compare names. Feedback takes every request id a turn produced. Seven more tools declare the shape of what comes back. And a person's omitted clan is their primary player's clan, or an honest refusal, never an alt's. Contract 3.18.0.