feat(phase-c): resolve &mut-access phase-b TODOs via handle setters

PHP mutator methods that the Phase B port could not call because only
&self / &dyn / Rc access was available. Resolved by the interior-mutation
APIs that already exist: handle &self setters (set_dist/source_reference,
set_requires/dev/references/stability_flags), Rc<RefCell<dyn InputInterface>>
.borrow_mut(), and get_installation_manager().borrow_mut() (build_package_map
passes an empty/canonical package list per upstream). composer.get_package()
returns &RootPackageInterfaceHandle, so the "&dyn" Phase B note was wrong.
factory's set_config_source/set_auth_config_source were already live code;
their stale TODOs are removed.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

1 files changed, 4 insertions, 8 deletions

diff --git a/crates/shirabe/src/downloader/git_downloader.rs b/crates/shirabe/src/downloader/git_downloader.rs
index 078ac3a..7dace1b 100644
--- a/crates/shirabe/src/downloader/git_downloader.rs
+++ b/crates/shirabe/src/downloader/git_downloader.rs
@@ -1000,11 +1000,9 @@ impl VcsDownloader for GitDownloader {
             self.update_to_commit(package.clone(), &path, &r#ref, &pretty_version)?
         {
             if package.get_dist_reference() == package.get_source_reference() {
-                // TODO(phase-b): set_dist_reference requires &mut PackageInterface
-                // package.set_dist_reference(Some(new_ref.clone()));
+                package.set_dist_reference(Some(new_ref.clone()));
             }
-            // package.set_source_reference(Some(new_ref));
-            let _ = new_ref;
+            package.set_source_reference(Some(new_ref));
         }
 
         Ok(None)
@@ -1125,11 +1123,9 @@ impl VcsDownloader for GitDownloader {
             self.update_to_commit(target.clone(), &path, &r#ref, &pretty_version)?
         {
             if target.get_dist_reference() == target.get_source_reference() {
-                // TODO(phase-b): set_dist_reference requires &mut PackageInterface
-                // target.set_dist_reference(Some(new_ref.clone()));
+                target.set_dist_reference(Some(new_ref.clone()));
             }
-            // target.set_source_reference(Some(new_ref));
-            let _ = new_ref;
+            target.set_source_reference(Some(new_ref));
         }
 
         let mut update_origin_url = false;