test(desktop): fence staged steering in slash-command E2E

Problem

The Desktop E2E test dispatches a staged slash command instead of steering it into a running turn is flaky under CI load.

Observed failure:

Locator: locator('.maka-quote-workbar-panel')
Expected: 1
Received: 0
Timeout: 10000ms

CI example: https://github.com/maka-agent/maka-agent/actions/runs/31593434388/job/94103386532

The focused test passes locally, including repeated runs, so this is timing-sensitive rather than a deterministic feature failure.

Introduction

The scenario was introduced by #2612. #2651 fixed an earlier readiness race in the same test—the test used to treat the Stop button as proof that the first Session was ready—but the later staged-steering submission still has no completion fence.

Root cause

The test submits /compact explain while a Turn is running and immediately starts the /side flow.

Composer form submission launches asynchronous sendCurrent() without awaiting it. While the first command is awaiting sessions.steer, sendPendingRef.current remains true. Under slower CI scheduling, the final Enter for /side discuss separately can arrive during that window; sendCurrent() rejects the overlapping submission, so no side-chat panel is created and the locator times out.

This explains why focused local runs pass: the steering IPC normally settles before the second Enter.

Suggested fix

Make the E2E wait for an observable completion boundary for the first staged steering submission before starting the /side command—for example, wait for its acknowledged steering output or another stable UI contract that proves sendPending has settled.

Avoid increasing the 10-second locator timeout: the missing panel is caused by an ignored overlapping submission, not slow panel rendering.

Acceptance criteria

• The test explicitly fences the first staged steering submission before submitting /side
• The focused scenario remains stable under repetition and CI load
• The assertion continues to verify that the staged command was routed as steering and that /side opens a side chat

问题

Desktop E2E 用例 dispatches a staged slash command instead of steering it into a running turn 在 CI 负载下存在不稳定失败。

观察到的失败：

Locator: locator('.maka-quote-workbar-panel')
Expected: 1
Received: 0
Timeout: 10000ms

CI 示例：https://github.com/maka-agent/maka-agent/actions/runs/31593434388/job/94103386532

该用例在本地定向及重复运行时可以通过，因此这是时序问题，不是确定性的功能失败。

引入来源

这个场景由 #2612 引入。#2651 修复了同一测试中更早的一处 readiness race——测试曾把 Stop 按钮出现误当成首个 Session 已就绪——但后续 staged steering 提交仍缺少完成边界。

根因

测试在 Turn 运行期间提交 /compact explain，随后立即开始 /side 流程。

Composer 的表单提交会启动异步 sendCurrent()，但事件处理本身不会等待它完成。在第一条命令等待 sessions.steer 时，sendPendingRef.current 会保持为 true。在较慢的 CI 调度下，最终提交 /side discuss separately 的 Enter 可能落入这个窗口；sendCurrent() 会拒绝重叠提交，因此 side-chat panel 根本没有被创建，locator 最终超时。

这也解释了为什么本地定向运行通常通过：steering IPC 往往能在第二次 Enter 前完成。

建议修复

E2E 在开始 /side 命令前，应等待第一条 staged steering 提交的可观察完成边界，例如等待对应的 acknowledged steering 输出，或等待另一个能稳定证明 sendPending 已结束的 UI 契约。

不建议单纯增加 10 秒 locator timeout：panel 缺失是因为重叠提交被忽略，而不是 panel 渲染较慢。

验收标准

• 测试在提交 /side 前显式等待第一条 staged steering 提交完成
• 定向重复运行和 CI 负载下保持稳定
• 仍然验证 staged command 被作为 steering 路由，并且 /side 能打开 side chat