refactor(composer): hold managers behind *Interface traits

Composer/PartialComposer exposed its RepositoryManager, InstallationManager,
EventDispatcher, Locker, DownloadManager, AutoloadGenerator and ArchiveManager
as concrete types, but Composer's public setters (setDownloadManager() etc.)
let plugins swap in subclasses. Introduce a *Interface trait per manager and
store each as Rc<RefCell<dyn ...Interface>> so a replacement is honored.

Only Composer's slots and the sinks fed from its accessors become trait
objects; managers injected concretely at construction keep their concrete
references, matching PHP semantics. Fluent setters on the affected classes now
return () and Locker::update_hash is de-generified to a boxed FnOnce so the
traits stay object-safe.

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

1 files changed, 3 insertions, 4 deletions

diff --git a/crates/shirabe/src/command/create_project_command.rs b/crates/shirabe/src/command/create_project_command.rs
index ab45400..abbf37a 100644
--- a/crates/shirabe/src/command/create_project_command.rs
+++ b/crates/shirabe/src/command/create_project_command.rs
@@ -865,7 +865,7 @@ impl CreateProjectCommand {
                     RepositoryFactory::default_repos(
                         Some(io.clone()),
                         Some(config.clone()),
-                        Some(&mut rm.borrow_mut()),
+                        Some(&mut *rm.borrow_mut()),
                     )?
                     .into_iter()
                     .map(|(_, v)| v)
@@ -998,9 +998,8 @@ impl CreateProjectCommand {
         }
 
         let dm = composer.get_download_manager();
-        dm.borrow_mut()
-            .set_prefer_source(prefer_source)
-            .set_prefer_dist(prefer_dist);
+        dm.borrow_mut().set_prefer_source(prefer_source);
+        dm.borrow_mut().set_prefer_dist(prefer_dist);
 
         let project_installer = ProjectInstaller::new(&directory, dm.clone(), fs.clone());
         let installation_manager = composer.get_installation_manager().clone();