feature: shorthand for --with (-w) in uvx and uv tool run (#14530)
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## Summary
This is a small quality of life feature that adds a shorthand (`-w`) to
the `--with` flag for minimizing keystrokes.
Pretty minor, but I didn't see any conflicts with `-w` and thought this
could be a nice place for it.
```bash
# proposed addition (short)
uvx -w numpy ipython
# original (long)
uvx --with numpy ipython
```
## Test Plan
Added testing already in the P.R. - just copied over tests from the
`--with` flag
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