feat(package): implement PackageInterface accessor layer for Package/CompletePackage/RootPackage

Fill the trait-impl todo!() across the package accessor layer so loaded
packages are actually usable (the ArrayLoader::load path depends on it):

- Package: implement BasePackage/PackageInterface from struct fields and
  existing inherent methods; Display via get_unique_name.
- CompletePackage: delegate PackageInterface to inner Package.
- RootPackage: delegate CompletePackageInterface/PackageInterface to inner
  CompletePackage; RootPackageInterface link setters delegate to Package.

Correct three unfaithful trait signatures found during implementation:

- get_target_dir returns Option<String> (PHP computes a normalized value;
  a borrow cannot represent it, and AliasPackage could not implement &str
  across its aliasOf handle).
- RootPackageInterface link setters take IndexMap<String, Link>, matching
  Package and the real ArrayLoader caller (PHP RootPackage inherits
  Package::setRequires; the Link[] docblock was imprecise).
- get_full_pretty_version takes a DisplayMode enum instead of a raw i64;
  the match is now exhaustive, so it returns String without an error path.

Move mirror conversion to the boundaries: PackageInterface mirror methods
use Vec<Mirror> (the typed form, matching the inherent methods), with
array<->Mirror conversion done by the producer (ComposerRepository) and
consumer (ArrayDumper).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

1 files changed, 10 insertions, 11 deletions

diff --git a/crates/shirabe/src/dependency_resolver/operation/update_operation.rs b/crates/shirabe/src/dependency_resolver/operation/update_operation.rs
index bc31256..104f4ef 100644
--- a/crates/shirabe/src/dependency_resolver/operation/update_operation.rs
+++ b/crates/shirabe/src/dependency_resolver/operation/update_operation.rs
@@ -2,7 +2,6 @@
 
 use crate::dependency_resolver::operation::OperationInterface;
 use crate::dependency_resolver::operation::SolverOperation;
-use crate::package::PackageInterface;
 use crate::package::PackageInterfaceHandle;
 use crate::package::version::VersionParser;
 
@@ -33,25 +32,25 @@ impl UpdateOperation {
         target_package: PackageInterfaceHandle,
         lock: bool,
     ) -> String {
-        let mut from_version = initial_package
-            .get_full_pretty_version(false, <dyn PackageInterface>::DISPLAY_SOURCE_REF);
-        let mut to_version = target_package
-            .get_full_pretty_version(false, <dyn PackageInterface>::DISPLAY_SOURCE_REF);
+        let mut from_version =
+            initial_package.get_full_pretty_version(false, crate::package::DisplayMode::SourceRef);
+        let mut to_version =
+            target_package.get_full_pretty_version(false, crate::package::DisplayMode::SourceRef);
 
         if from_version == to_version
             && initial_package.get_source_reference() != target_package.get_source_reference()
         {
             from_version = initial_package
-                .get_full_pretty_version(true, <dyn PackageInterface>::DISPLAY_SOURCE_REF);
+                .get_full_pretty_version(true, crate::package::DisplayMode::SourceRef);
             to_version = target_package
-                .get_full_pretty_version(true, <dyn PackageInterface>::DISPLAY_SOURCE_REF);
+                .get_full_pretty_version(true, crate::package::DisplayMode::SourceRef);
         } else if from_version == to_version
             && initial_package.get_dist_reference() != target_package.get_dist_reference()
         {
-            from_version = initial_package
-                .get_full_pretty_version(true, <dyn PackageInterface>::DISPLAY_DIST_REF);
-            to_version = target_package
-                .get_full_pretty_version(true, <dyn PackageInterface>::DISPLAY_DIST_REF);
+            from_version =
+                initial_package.get_full_pretty_version(true, crate::package::DisplayMode::DistRef);
+            to_version =
+                target_package.get_full_pretty_version(true, crate::package::DisplayMode::DistRef);
         }
 
         let action_name = if VersionParser::is_upgrade(