Agent Skills: narrative-handoff-contract

Defines and validates the machine-readable contract that passes a narrative architecture between a structural agent and a drafting agent — architecture.json with evidence-backed slots, capped scene tags, gap dispositions, a DEAD column, and an escalation object for sending defects back upward. Ships a validator script so the rules are enforced rather than requested. Use when two agents or two sessions must hand narrative work to each other, when an architecture needs checking before drafting begins, when a draft must report a defect it cannot fix at its own layer, or when the user mentions handoff, contract, schema, validator, architecture.json, escalation, or "the outline and the draft have drifted apart".