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, 2 insertions, 2 deletions

diff --git a/crates/shirabe/src/repository/repository_set.rs b/crates/shirabe/src/repository/repository_set.rs
index ba6373a..393639f 100644
--- a/crates/shirabe/src/repository/repository_set.rs
+++ b/crates/shirabe/src/repository/repository_set.rs
@@ -15,7 +15,7 @@ use crate::dependency_resolver::PoolOptimizer;
 use crate::dependency_resolver::Request;
 use crate::dependency_resolver::SecurityAdvisoryPoolFilter;
 use crate::downloader::TransportException;
-use crate::event_dispatcher::EventDispatcher;
+use crate::event_dispatcher::EventDispatcherInterface;
 use crate::io::IOInterface;
 use crate::io::NullIO;
 use crate::package::AliasPackageHandle;
@@ -451,7 +451,7 @@ impl RepositorySet {
         &mut self,
         request: &mut Request,
         io: std::rc::Rc<std::cell::RefCell<dyn IOInterface>>,
-        event_dispatcher: Option<std::rc::Rc<std::cell::RefCell<EventDispatcher>>>,
+        event_dispatcher: Option<std::rc::Rc<std::cell::RefCell<dyn EventDispatcherInterface>>>,
         pool_optimizer: Option<PoolOptimizer>,
         ignored_types: Vec<String>,
         allowed_types: Option<Vec<String>>,