v0.3.5 — write the handoff now, copy the opener

v0.3.5 — the banner now gives you two choices

At a level crossing the banner used to offer only "got it". Now:

• Write the handoff, I will copy it — the host writes one machine-facts handoff draft
  immediately (skipping the "only refresh after another step" gate) and surfaces a copy-ready opener.
• Got it — unchanged: close the banner, no side effect.

The opener (English UI):

@HANDOVER.md Continue from this handoff. Fill in the "to fill in" slots first, then carry on with the task.

Paste it as the first message of the new session. That is what makes the model finish the
conclusions — the plugin still registers no tool and injects no prompt, so context tax stays zero.

Under the hood: POST /api/context-guard/draft?sessionId=… forces one draft; it honours
handoverOnWarn and the pending lock, writes machine facts only, and returns a file name only
(never an absolute path — same rule as the state route).

Tests: the fake-host selftest now drives the real handler (405/400, no-reading, a real write at 10%
occupancy, and a check that no absolute path leaks). 73 → 81 checks; unit 51 pass / 1 skipped.

中文

v0.3.5 —— banner 现在给你两个选择

上下文跨档时，原来只能点「知道了」；现在：

• 写好交接，我复制 —— 宿主立刻写一次机器事实交接草稿（跳过"水位涨够才刷"的步进闸门），
  并把一段可复制的开场白摆出来。
• 知道了 —— 与旧版一致：关闭提示，无附带动作。

可复制的开场白（中文界面）：

@HANDOVER.md 接着这份交接继续。请先把「待补」补完再继续任务。

贴进新会话的第一条输入即可。让模型动手的那一下发生在你粘贴时 ——
插件仍然不注册工具、不注入 prompt，上下文税保持为 0。

实现：POST /api/context-guard/draft?sessionId=… 强制起草一次；尊重 handoverOnWarn 与 pending 锁，
只写机器事实，响应里只有文件名（绝不回绝对路径，与状态路由同一条规矩）。

测试：假宿主自检现在驱动真 handler（405/400、no-reading、10% 水位下真写文件、以及"响应不含绝对路径"）。
自检 73 → 81 项；单测 51 通过 / 1 跳过。