docs: align runtime-context contracts

packages/pty/pty-local/README.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/pty/pty-local/README.md
-README.md: 4c200743732e62d8e76afd1a055943dac5f141b0
-README.zh.md: 0fbcc0eb8c0b5ddb89e62b4e748d1bd280b50b36
+README.md: ba05495318127b63b3d2a6a60ec743e1ff1c5821
+README.zh.md: 81987ea0685d761507b535b7ed6eefa0888fbd54

packages/pty/pty-local/README.md

@@ -26,7 +26,7 @@ The current-policy clause is present while this backend is mounted. Retained PTY
 
 #### KV Cache effect
 
-A standing-policy change updates the owner-rendered request prefix; consumer results remain append-only.
+A standing-policy change appends an owner-rendered superseding runtime-context snapshot after retained history; consumer results remain append-only.
 
 ## Known Limitations and Deferred Work
 

packages/pty/pty-local/README.zh.md

@@ -26,7 +26,7 @@ Linux 的就绪检测结合以下机制：由前台状态验证的私有 bash
 
 #### KV Cache 影响
 
-常驻策略发生变化时，归属方渲染的请求前缀会更新；消费方结果保持仅追加。
+常驻策略发生变化时，会在保留的历史之后追加一份由归属方渲染、取代先前状态的运行时上下文快照；消费方结果保持仅追加。
 
 ## 已知限制与暂缓事项