Include uv's target triple in version report (#18520)
When looking at https://github.com/astral-sh/uv/issues/18509 I realized
this would be useful
e.g.,
```
$ uv self version
0.0.0 (53b0f5d92 2023-10-19 x86_64-unknown-linux-gnu)
```
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Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Aria Desires <aria.desires@gmail.com>
