Anti-AI-slop rules.

Concrete, checkable rules that distinguish "designed by a human who has shipped product" from "default LLM output." Several rules below are auto-enforced by the daemon's lint-artifact linter — failing an enforced rule is not a style preference, it is a regression. The rest are guidance for agents and reviewers and are flagged inline as "(guidance, not auto-checked)" so the contract with the linter stays honest.