Fix `uv tree --invert` for platform dependencies (#7808)
## Summary
`click` has one dependency of `colorama` only on Windows, `uv tree
--invert` should not include `colorama` on non-Windows platforms, but
currently:
```console
$ uv init
$ uv add click
$ uv tree --invert --python-platform macos
colorama v0.4.6
```
it should:
```console
$ uv tree --invert --python-platform macos
click v8.1.7
└── project v0.1.0
```
