Add uv- prefix to all internal crates (#7853)

## Summary

Brings more consistency to the repo and ensures that all crates
automatically show up in `--verbose` logging.

crates/uv-python/src/virtualenv.rs

@@ -4,8 +4,8 @@ use std::{
 };
 
 use fs_err as fs;
-use pypi_types::Scheme;
 use thiserror::Error;
+use uv_pypi_types::Scheme;
 
 /// The layout of a virtual environment.
 #[derive(Debug)]