fix(repository): run lazy initialization in count/has_package

PHP's ArrayRepository::count()/hasPackage() call $this->initialize(),
which late-binds to the concrete repository class and lazily loads its
packages. The Rust pass-throughs skipped that: they ran ArrayRepository's
stub initialize instead, returning 0/false and marking the repository
initialized with an empty package list, which made ensure_initialized()
skip the real initialization forever after.

Take &mut self in RepositoryInterface::count/has_package so the lazy
repositories (Filesystem, Platform, Composer) can guard with their real
initialize, and return Result from has_package since that initialization
can fail (PHP propagates the exception). InstallerInterface::is_installed
and InstallationManager::is_package_installed/mark_alias_installed
propagate the same way, which also resolves the TODO(phase-d) markers on
Package/Path/Artifact/Vcs repositories about initialization errors being
swallowed.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/crates/shirabe/tests/advisory/auditor_test.rs b/crates/shirabe/tests/advisory/auditor_test.rs
index adc90a4d..65e848dd 100644
--- a/crates/shirabe/tests/advisory/auditor_test.rs
+++ b/crates/shirabe/tests/advisory/auditor_test.rs
@@ -144,10 +144,10 @@ impl AdvisoryProviderInterface for MockAdvisoryRepository {
 }
 
 impl RepositoryInterface for MockAdvisoryRepository {
-    fn count(&self) -> anyhow::Result<usize> {
+    fn count(&mut self) -> anyhow::Result<usize> {
         unimplemented!("not used by Auditor")
     }
-    fn has_package(&self, _package: PackageInterfaceHandle) -> bool {
+    fn has_package(&mut self, _package: PackageInterfaceHandle) -> anyhow::Result<bool> {
         unimplemented!("not used by Auditor")
     }
     fn find_package(