feat(composite-repository): forward remove_package to writable repos

Resolve the phase-b TODO by adding an as_writable_repository_interface_mut
downcast helper on RepositoryInterface, mirroring PHP's instanceof
WritableRepositoryInterface check, and propagate inner errors.

1 files changed, 5 insertions, 0 deletions

diff --git a/crates/shirabe/src/repository/installed_filesystem_repository.rs b/crates/shirabe/src/repository/installed_filesystem_repository.rs
index 84bf1ca..1f6be2c 100644
--- a/crates/shirabe/src/repository/installed_filesystem_repository.rs
+++ b/crates/shirabe/src/repository/installed_filesystem_repository.rs
@@ -161,6 +161,11 @@ impl RepositoryInterface for InstalledFilesystemRepository {
     ) -> Option<&mut dyn InstalledRepositoryInterface> {
         Some(self)
     }
+    fn as_writable_repository_interface_mut(
+        &mut self,
+    ) -> Option<&mut dyn crate::repository::WritableRepositoryInterface> {
+        Some(self)
+    }
     fn as_any(&self) -> &dyn std::any::Any {
         todo!()
     }