{
  "$comment": "修订项合同（专题-09 §4.3）。original_exact 必须覆盖对应发现的至少一个 span（允许紧邻标点的最小扩展，U0 修正 #6），且在当前文本中唯一匹配。",
  "type": "object",
  "required": ["finding_id", "action", "original_exact", "replacement", "rationale", "protected_invariants"],
  "properties": {
    "finding_id": {"type": "string", "minLength": 1},
    "action": {"type": "string", "enum": ["skip", "delete", "compress", "local_rewrite", "patch", "structural_proposal"]},
    "original_exact": {"type": "string", "minLength": 1},
    "replacement": {"type": "string"},
    "rationale": {"type": "string", "minLength": 2},
    "protected_invariants": {"type": "array", "items": {"type": "string"}}
  }
}