Check nested IO errors for retries (#13260)
## Summary
The only thing that changed for #12175 relevant to the existing
downloads is the order of nesting, so we're checking all nested IO
errors instead of only the first one.
See #13238
## Test Plan
This is an educated guess based on what happens if I turn off the
network during a download.
```
Downloading cpython-3.13.3-linux-x86_64-gnu (download) (20.3MiB)
TRACE Considering retry of error: ExtractError("cpython-3.13.3-20250409-x86_64-unknown-linux-gnu-install_only_stripped.tar.gz", Io(Custom { kind: Other, error: TarError { desc: "failed to unpack `/home/konsti/.local/share/uv/python/.temp/.tmpe3AIvt/python/lib/libpython3.13.so.1.0`", io: Custom { kind: Other, error: TarError { desc: "failed to unpack `python/lib/libpython3.13.so.1.0` into `/home/konsti/.local/share/uv/python/.temp/.tmpe3AIvt/python/lib/libpython3.13.so.1.0`", io: Custom { kind: Other, error: reqwest::Error { kind: Decode, source: reqwest::Error { kind: Body, source: TimedOut } } } } } } }))
TRACE Cannot retry IO error: not one of `ConnectionReset` or `UnexpectedEof`
TRACE Cannot retry IO error: not one of `ConnectionReset` or `UnexpectedEof`
TRACE Cannot retry error: not an IO error
error: Failed to install cpython-3.13.3-linux-x86_64-gnu
Caused by: Failed to extract archive: cpython-3.13.3-20250409-x86_64-unknown-linux-gnu-install_only_stripped.tar.gz
Caused by: failed to unpack `/home/konsti/.local/share/uv/python/.temp/.tmpe3AIvt/python/lib/libpython3.13.so.1.0`
Caused by: failed to unpack `python/lib/libpython3.13.so.1.0` into `/home/konsti/.local/share/uv/python/.temp/.tmpe3AIvt/python/lib/libpython3.13.so.1.0`
Caused by: error decoding response body
Caused by: request or response body error
Caused by: operation timed out
```
