refactor(desktop): retire obsolete Astryx workarounds

[M4n5ter]

English

Summary

Retire three compatibility rules whose contracts are now owned by the pinned Astryx 0.5.2 dependency:

• remove the sidebar and ModulePage resize-hit-area overrides fixed upstream in Astryx 0.5.0;
• remove the ChatLayout flex shim fixed upstream in Astryx 0.3.0;
• delete the compositor-sensitive two-direction resize E2E and its test-only exports, while retaining the product-owned sidebar footer geometry test.

Fixes #4622

Root cause

Dependency upgrades did not discharge Maka's temporary compatibility rules. The resize E2E was added after the pinned Astryx package already contained and tested the hit-area fix, so it duplicated vendor behavior through two synthetic Electron drags. The reverse-drag flake exposed that stale ownership boundary; adding more timing or diagnostics would preserve it.

Audit boundary

The broader Desktop E2E audit found no other confirmed obsolete test. The streaming quote fixme still reproduced once in an 8-run, 4-worker probe, and the [hidden] override remains necessary because Astryx still uses a zero-specificity :where([hidden]) reset.

Verification

• npm --workspace @maka/desktop run e2e -- e2e/sidebar-geometry.spec.ts --workers=1 — full Desktop build passed; retained footer test passed.
• Targeted real-window checks for Module Hub, prompt-rail scrollport geometry, and streaming tail following — 3 passed.
• npm --workspace @maka/desktop run typecheck — passed.
• npx knip --workspace apps/desktop — passed.
• Biome on all six changed files — passed.
• git diff --check — passed.

AI use

• No generative tool made a substantive contribution
• Generative tooling made a substantive contribution

Tool(s) and scope: OpenAI Codex traced dependency and test history, audited adjacent E2E and compatibility rules, removed confirmed obsolete paths, ran verification, and prepared this pull request.

Checklist

• Tests cover the change and fail without it — intentionally not applicable: this change removes tests and shims whose behavior is owned upstream.
• Lint, format, typecheck and the affected suites pass locally.

Does this PR entail a change in behavior?

• Yes — resize and chat layout now use Astryx's fixed implementations without Maka overrides.
• No

中文

摘要

删除三处已由当前 Astryx 0.5.2 依赖承担的兼容规则：

• 删除 Astryx 0.5.0 已修复的 sidebar 和 ModulePage resize hit-area override；
• 删除 Astryx 0.3.0 已修复的 ChatLayout flex shim；
• 删除依赖 compositor 时序的双向 resize E2E 及其测试专用导出，保留 Maka 自己负责的 sidebar footer 几何测试。

Fixes #4622

根因

依赖升级后没有及时卸载 Maka 的临时兼容规则。resize E2E 新增时，锁定的 Astryx 已包含并测试该 hit-area 修复，因此这条测试只是通过两次 Electron 合成拖动重复验证上游行为。反向拖动 flake 暴露的是过期的责任边界；继续增加时序处理或诊断只会将它固化。

审计边界

更广的 Desktop E2E 审计没有发现其他已确认过时的测试。streaming quote fixme 在 4 worker、8 次 probe 中仍复现 1 次；[hidden] override 也仍有必要，因为 Astryx 当前仍使用零优先级的 :where([hidden]) reset。

验证

• npm --workspace @maka/desktop run e2e -- e2e/sidebar-geometry.spec.ts --workers=1 — Desktop 完整构建通过，保留的 footer 测试通过。
• Module Hub、prompt rail scrollport 几何和 streaming tail following 三条定向真实窗口测试 — 3 条通过。
• npm --workspace @maka/desktop run typecheck — 通过。
• npx knip --workspace apps/desktop — 通过。
• 六个改动文件的 Biome 检查 — 通过。
• git diff --check — 通过。

AI 使用

• 无生成式工具做出实质贡献
• 生成式工具做出了实质贡献

工具及范围：OpenAI Codex 追溯了依赖和测试历史，审计了相邻 E2E 和兼容规则，删除已确认过时的路径，完成验证并准备本 PR。

检查清单

• 测试覆盖改动且在改动前失败 — 特意不适用：本改动删除由上游承担行为的测试和 shim。
• 本地 lint、format、typecheck 和受影响测试均通过。

本 PR 是否改变行为？

• 是 — resize 和 chat layout 现在直接使用 Astryx 的已修复实现，不再受 Maka override 影响。
• 否

[Astro-Han]

LGTM