Respect static metadata for already-installed distributions (#10242)

## Summary

Closes
https://github.com/astral-sh/uv/issues/10239#issuecomment-2565663046

crates/uv-distribution/src/distribution_database.rs

@@ -21,7 +21,8 @@ use uv_client::{
 };
 use uv_distribution_filename::WheelFilename;
 use uv_distribution_types::{
-    BuildableSource, BuiltDist, Dist, FileLocation, HashPolicy, Hashed, Name, SourceDist,
+    BuildableSource, BuiltDist, Dist, FileLocation, HashPolicy, Hashed, InstalledDist, Name,
+    SourceDist,
 };
 use uv_extract::hash::Hasher;
 use uv_fs::write_atomic;
@@ -115,6 +116,32 @@ impl<'a, Context: BuildContext> DistributionDatabase<'a, Context> {
         }
     }
 
+    /// Either fetch the only wheel metadata (directly from the index or with range requests) or
+    /// fetch and build the source distribution.
+    ///
+    /// While hashes will be generated in some cases, hash-checking is only enforced for source
+    /// distributions, and should be enforced by the caller for wheels.
+    #[instrument(skip_all, fields(%dist))]
+    pub async fn get_installed_metadata(
+        &self,
+        dist: &InstalledDist,
+    ) -> Result<ArchiveMetadata, Error> {
+        // If the metadata was provided by the user directly, prefer it.
+        if let Some(metadata) = self
+            .build_context
+            .dependency_metadata()
+            .get(dist.name(), Some(dist.version()))
+        {
+            return Ok(ArchiveMetadata::from_metadata23(metadata.clone()));
+        }
+
+        let metadata = dist
+            .metadata()
+            .map_err(|err| Error::ReadInstalled(Box::new(dist.clone()), err))?;
+
+        Ok(ArchiveMetadata::from_metadata23(metadata))
+    }
+
     /// Either fetch the only wheel metadata (directly from the index or with range requests) or
     /// fetch and build the source distribution.
     ///

crates/uv-distribution/src/error.rs

@@ -8,7 +8,7 @@ use zip::result::ZipError;
 use crate::metadata::MetadataError;
 use uv_client::WrappedReqwestError;
 use uv_distribution_filename::WheelFilenameError;
-use uv_distribution_types::IsBuildBackendError;
+use uv_distribution_types::{InstalledDist, InstalledDistError, IsBuildBackendError};
 use uv_fs::Simplified;
 use uv_normalize::PackageName;
 use uv_pep440::{Version, VersionSpecifiers};
@@ -82,6 +82,8 @@ pub enum Error {
     Metadata(#[from] uv_pypi_types::MetadataError),
     #[error("Failed to read metadata: `{}`", _0.user_display())]
     WheelMetadata(PathBuf, #[source] Box<uv_metadata::Error>),
+    #[error("Failed to read metadata from installed package `{0}`")]
+    ReadInstalled(Box<InstalledDist>, #[source] InstalledDistError),
     #[error("Failed to read zip archive from built wheel")]
     Zip(#[from] ZipError),
     #[error("Source distribution directory contains neither readable `pyproject.toml` nor `setup.py`: `{}`", _0.user_display())]