I would be great to have multilanguage support for dictation.

It would be great to have multilanguage support for dictation. For example codex has it. But Github copilot app tries to transcribe as English

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| Field | Value |
| --- | --- |
| App version | 1.0.17 |
| OS | macOS 26.5.2 |
| Theme | ABOLKOG |
| Path | /chat |
| Tenure | Week 5 |

从 macOS 上的 /chat 听写流程入手，确定当前的转录语言是如何选择的。Issue 未指定文件或测试，因此首先梳理现有的听写路径，并明确预期支持哪些语言以及选择行为。完成的标准是：非英语听写能够被正确转录，并且在 macOS 上验证支持的行为。

由索引模型根据 Issue 内容生成。