v0.12.152: @newsroom.writer: our first customers

Our first customers: the brief for an early access programme for Agent Behaviour Policies. The first group are customers, not beta users: each starts with credit on a site that meters and bills, follows a start-here page, and is followed closely, with objectives and milestones of their own. The aim is the usage moment: the simplest useful policy, the entry point with least friction, and a fair price. A mailing list keeps everyone else for the next batch. Two figures, the journey and the batches, both marked proposed.