## Summary
This is an intermediary change in enabling universal resolution for
`requirements.txt` files. To start, we need to be able to preserve
markers in the `requirements.txt` output _and_ propagate those markers,
such that if you have a dependency that's only included with a given
marker, the transitive dependencies respect that marker too.
Closes#1429.
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## Summary
Resolves https://github.com/astral-sh/uv/issues/4439 partially.
Implements for `uv pip tree`:
- `--no-dedupe` flag, similar to `cargo tree --no-dedupe` .
- denote dependency cycles with `(#)` and add a footnote if there's a
cycle (using `(*)` would require keeping track of the cycle state, so
opted to do this instead).
<!-- What's the purpose of the change? What does it do, and why? -->
## Test Plan
The existing tests pass + added a couple of tests to validate
`--no-dedupe` behavior.
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## Summary
This PR moves all the CLI code into its own crate, separate from the
`uv` crate. The `uv` crate is iterated on frequently, and the CLI code
comprises a significant portion of it but rarely changes. Removing the
CLI code reduces the `uv` crate size from 1.4MiB to 1.0MiB.
