[App][i18n] zh-CN renders both xhigh and ultra reasoning efforts as “极高”

What version of the Codex App are you using (From “About Codex” dialog)?

Codex Windows app 26.707.3563.0

What subscription do you have?

Not account-specific. The issue was reproduced with an account that has access to GPT-5.6 Sol.

What platform is your computer?

Microsoft Windows NT 10.0.19045.0 x64 (Windows 10 Home China, build 19045)

What issue are you seeing?

With the Codex App locale set to Simplified Chinese (zh-CN), the reasoning-effort menu for GPT-5.6 Sol shows these labels:

轻度
中
高
极高
极高
  更快消耗使用额度

The fourth and fifth options are different reasoning efforts (xhigh and ultra), but both render as 极高. The last option is identifiable as ultra because it carries the extra-usage warning. This makes the options and the selected value ambiguous.

The bundled localization catalog in this build confirms the collision:

xhigh -> 极高
max   -> 最高
ultra -> 极高

The default English labels are Extra High, Max, and Ultra. The Traditional Chinese (zh-TW) catalog already keeps the three values distinct:

xhigh -> 極高
max   -> 最高
ultra -> 超高

What steps can reproduce the bug?

1. Set the Codex App locale to Simplified Chinese (zh-CN).
2. Start or open a task using GPT-5.6 Sol.
3. Open the model and reasoning controls.
4. Open the reasoning-effort submenu.
5. Observe two consecutive entries labeled 极高; the second one has the 更快消耗使用额度 warning.

What is the expected behavior?

Every supported reasoning effort should have a distinct localized label. A consistent mapping would be:

xhigh -> 极高
max   -> 最高
ultra -> 超高

In particular, composer.mode.local.reasoning.ultra.label should not use the same translation as composer.mode.local.reasoning.xhigh.label.

Additional information

• ReasoningEffort already models xhigh, max, and ultra as distinct values in the public protocol: https://github.com/openai/codex/blob/main/codex-rs/protocol/src/openai_models.rs
• zh-HK appears to have the same xhigh/ultra collision (極高 for both), while zh-TW already uses 超高 for ultra.
• Suggested regression coverage: assert the zh-CN labels for xhigh, max, and ultra, and add a picker snapshot containing the Ultra usage warning.
• Related to the broader Chinese-localization report #27244, but this is a separate, deterministic wrong-label bug.