AI Assistant: translate to chinese fails consistently

Asking for a translation to chinese fails consistently, resulting on the following error message:


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Steps to reproduce:

- get a piece of content on the editor
- use the AI Assistant extension to request a translation to chinese
- experiment translating to other languages before asking the chinese version
- the failure will happen consistently

Start by reproducing the failure in the editor with the AI Assistant extension, following the listed sequence of translations and reviewing the error shown in the issue. The work is done when requesting a Chinese translation succeeds consistently, including after translating to other languages.

Written by the indexing model from the issue text.