A second native client is starting, and the rules that keep the first
one aligned with the server lived in issue threads and habit. They are
now docs/CONTRIBUTING-CLIENTS.md: where the contract truth lives, the
response envelope, auth from a client's point of view, sync semantics,
the server-authoritative-values rule, and how cross-repo coordination
works in practice.
CONTRIBUTING-AI.md was a snapshot of an old conventions document and
had drifted well away from the codebase it describes (it still spoke
of 26 Prisma models and in-memory rate limits). It now points at the
living sources instead of carrying an aging copy.