feat(filter): share platform req filter via Rc, drop clone_box

PlatformRequirementFilterInterface::clone_box (a todo!() trait-object
clone stub) is removed in favor of Rc<dyn ...> shared ownership, matching
PHP's by-reference sharing of the single filter object. Box<dyn ...> is
replaced with Rc<dyn ...> across the factory, Solver/RuleSetGenerator,
VersionSelector, AutoloadGenerator, Installer and the command layer
(BaseCommand/PackageDiscoveryTrait and their impls); clone_box call
sites become Rc clones.

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/package/version/version_selector.rs b/crates/shirabe/src/package/version/version_selector.rs
index d2a551f..31942f9 100644
--- a/crates/shirabe/src/package/version/version_selector.rs
+++ b/crates/shirabe/src/package/version/version_selector.rs
@@ -65,7 +65,7 @@ impl VersionSelector {
         package_name: &str,
         target_package_version: Option<&str>,
         preferred_stability: &str,
-        platform_requirement_filter: Option<Box<dyn PlatformRequirementFilterInterface>>,
+        platform_requirement_filter: Option<std::rc::Rc<dyn PlatformRequirementFilterInterface>>,
         repo_set_flags: i64,
         io: Option<std::rc::Rc<std::cell::RefCell<dyn IOInterface>>>,
         show_warnings: shirabe_php_shim::PhpMixed,
@@ -81,7 +81,7 @@ impl VersionSelector {
             .into());
         }
 
-        let platform_requirement_filter: Box<dyn PlatformRequirementFilterInterface> =
+        let platform_requirement_filter: std::rc::Rc<dyn PlatformRequirementFilterInterface> =
             match platform_requirement_filter {
                 Some(f) => f,
                 None => PlatformRequirementFilterFactory::ignore_nothing(),