Add override namespace to pyproject.toml/uv.toml (#3839)
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## Summary
See #3834 .
This PR adds a new namespace, `override-dependencies`, to
pyproject.toml/uv.toml.
This namespace assumes that the dependencies you want to override are
written in the form of `requirements.txt`.
a example of pyproject.toml
```toml
[project]
name = "example"
version = "0.0.0"
dependencies = [
"flask==3.0.0"
]
[tool.uv]
override-dependencies = [
"werkzeug==2.3.0"
]
```
This will improve usability by allowing you to override dependencies
without having to specify the --override option when running `uv pip
compile/install`.
## Test Plan
added test to `crates/uv/tests/pip_compile.rs`.
---------
Co-authored-by: konstin <konstin@mailbox.org>
