perf(package): hand out link maps behind Rc

PackageInterface::getRequires() and friends return the array of Link objects;
in PHP that is a copy-on-write array of object references, so a caller pays
nothing to look at it. The port returned IndexMap<String, Link> by value, so
every call deep-cloned the whole map, keys and constraints included. Pool
building calls these accessors once per package per candidate, which put
IndexMap::clone at 13.5% of `require laravel/laravel`.

Store the maps as Rc<IndexMap<String, Link>> and return a handle. Callers that
mutate the map clone it explicitly at the point of mutation, matching where PHP
would separate the array.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

1 files changed, 6 insertions, 3 deletions

diff --git a/crates/shirabe/src/command/bump_command.rs b/crates/shirabe/src/command/bump_command.rs
index 8f95366f..71ee2ffe 100644
--- a/crates/shirabe/src/command/bump_command.rs
+++ b/crates/shirabe/src/command/bump_command.rs
@@ -167,10 +167,13 @@ impl BumpCommand {
         let bumper = VersionBumper;
         let mut tasks = indexmap::IndexMap::new();
         if !dev_only {
-            tasks.insert("require", composer.get_package().get_requires());
+            tasks.insert("require", (*composer.get_package().get_requires()).clone());
         }
         if !no_dev_only {
-            tasks.insert("require-dev", composer.get_package().get_dev_requires());
+            tasks.insert(
+                "require-dev",
+                (*composer.get_package().get_dev_requires()).clone(),
+            );
         }
 
         let packages_filter = if !packages_filter.is_empty() {
@@ -196,7 +199,7 @@ impl BumpCommand {
         let mut updates: indexmap::IndexMap<&str, indexmap::IndexMap<String, String>> =
             indexmap::IndexMap::new();
         for (key, reqs) in &tasks {
-            for (pkg_name, link) in reqs {
+            for (pkg_name, link) in reqs.iter() {
                 if PlatformRepository::is_platform_package(pkg_name) {
                     continue;
                 }