Show query time and fix context name in recent queries

[skimmilk09]

The context name never showed up in the recent queries list. The template checked prev.context_name, but get_queries() in code_queries/data.py selects that column as t.context_name AS context, so the condition was always false.

I also added the query timestamp above the context line, using the existing localtime filter (t.query_time AS time).

Both changes are in one commit since they touch the same few lines, but I can split them if you'd rather review them separately.

mypy passes (90 files) and pytest passes (170 tests) locally.

I wasn't sure about the placement or styling of the timestamp, so let me know if you want it somewhere else in the entry.

[github-actions]

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[skimmilk09]

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[liffiton]

Thanks! Looks better. Looking at the design now that the context actually shows up, I think I'd like the context deemphasized a bit like the date is now. So maybe put it in the same line with the date, same formatting, and, if a context is present, separated by a pipe character (see if that looks alright) from the date. So "2026-08-03 | Context: whatever" maybe.

And something to look at next if you have time is the consistency between the designs for recent queries in Code Q&A and recent chats in the Tutors component. Doesn't have to be in this PR, necessarily, though could be if you want to fold it in.