Harden dev-flow: pre-authorization marker, alternatives log, check script

- Record rejected answers in decision.md at the moment they are rejected

- Allow explicit pre-authorized Build via a pre-authorized marker line

- Land scripts/check-dev-flow.sh and derive devflow/index.md from archives

- Add dev-flow process artifacts (decisions, prd) for open changes

openspec/changes/archive/2026-09-18-migrate-devflow-archives/tasks.md

@@ -0,0 +1,11 @@
+# Tasks: migrate-devflow-archives
+
+- [x] 1. Think:写 proposal.md + decision.md 的 Problem/Alternatives(迁移规则作为备选记录)
+- [x] 2. 确认点 1:汇报方案,获得授权并记录
+- [x] 3. 单样本:knowledge-index-panel/decision.md 迁移自 ADR-0001(五节转译,Q&A 备选,migrated-from 溯源)
+- [x] 4. 单样本:prd.md 收存进 change 目录
+- [x] 5. glossary/CONTEXT.md 的 ADR-0001 引用更新为新路径
+- [x] 6. design.md(迁移规则细节)与 tasks.md 落盘
+- [x] 7. Close:补齐本 change decision.md 的 Decision/Consequences/Verification
+- [x] 8. 验证:`check-dev-flow.sh knowledge-index-panel` 与 `check-dev-flow.sh migrate-devflow-archives` 均通过;`--index` 重生成
+- [x] 9. 确认点 2:汇报产物与剩余风险,用户确认归档(2026-09-18,"继续")