respect --project during uv python find (astral-sh#11990)

## Summary

this pr updates a couple discovery-related functions to accept a directory argument, used as the root directory when searching for a virtual environment

## Test Plan

todo

Author: thejchap

crates/uv-python/src/discovery.rs

@@ -29,7 +29,7 @@ use crate::managed::ManagedPythonInstallations;
 use crate::microsoft_store::find_microsoft_store_pythons;
 use crate::virtualenv::Error as VirtualEnvError;
 use crate::virtualenv::{
-    conda_environment_from_env, virtualenv_from_env, virtualenv_from_working_dir,
+    conda_environment_from_env, virtualenv_from_dir, virtualenv_from_env,
     virtualenv_python_executable, CondaEnvironmentKind,
 };
 #[cfg(windows)]
@@ -270,7 +270,7 @@ fn python_executables_from_virtual_environments<'a>(
     .flatten();
 
     let from_discovered_environment = iter::once_with(|| {
-        virtualenv_from_working_dir()
+        virtualenv_from_dir(crate::current_dir()?)
             .map(|path| {
                 path.map(virtualenv_python_executable)
                     .map(|path| (PythonSource::DiscoveredEnvironment, path))

crates/uv-python/src/virtualenv.rs

@@ -121,10 +121,11 @@ pub(crate) fn conda_environment_from_env(kind: CondaEnvironmentKind) -> Option<P
 /// Searches for a `.venv` directory in the current or any parent directory. If the current
 /// directory is itself a virtual environment (or a subdirectory of a virtual environment), the
 /// containing virtual environment is returned.
-pub(crate) fn virtualenv_from_working_dir() -> Result<Option<PathBuf>, Error> {
-    let current_dir = crate::current_dir()?;
 
-    for dir in current_dir.ancestors() {
+pub(crate) fn virtualenv_from_dir(dir: impl AsRef<Path>) -> Result<Option<PathBuf>, Error> {
+    let dir = dir.as_ref();
+
+    for dir in dir.ancestors() {
         // If we're _within_ a virtualenv, return it.
         if dir.join("pyvenv.cfg").is_file() {
             return Ok(Some(dir.to_path_buf()));