CIE-Unified

docs: 锁定施工合同——README补充宪法声明, LOCKED_IMPLEMENTATION_SPEC三方签定(含sedimentation_trace), 删除旧LOCKED_SPEC

docs: LOCKED_SPEC——双分支共同约束(待三方审定)

docs: CIE统一设计文档——三核三层一带