Translation is the last step of a search, not the first. Doing it earlier throws away the best pages.
An Arabic-speaking reader asking about a Node.js release wants the answer in Arabic. The best pages on the subject are in English. Translate the question first and the search finds worse pages; translate nothing and the reader gets an answer they cannot use.
The right order is: search in the question's own language, read the best sources whatever language they are in, and write the answer in the language the reader asked for.
What changes and what does not
Only the writing changes. Proper names, product names, codes, identifiers and quoted values stay exactly as the sources have them; a version number is not translated. The sources are listed with their own titles. The price is the same.
Saying which language applied
When no language is asked for, the answer is in the question's language, and the response says which one that was when the script makes it unambiguous: Arabic, Cyrillic, Devanagari, Japanese, Chinese. Latin script is shared by too many languages to guess, so the response stays silent rather than wrong.
A fixed list, on purpose
The languages offered are a short, fixed list declared in one place in the code. A language is added when the model writes it well, which is something to test, not a switch to flip. A value outside the list is refused before any work is done.