feat(plugin): carry Http\Response across as a materialized value

A response is built for one request and the graph never retains it, so there
is no entity for a handle to point at. The child holds a real instance
instead, revived from the object record the wire carries, and collect() frees
the copy each world holds — which is what that method is for. The
value-object rule rejects the class only because collect() assigns to $this,
so the category comes from an overrides.list entry.

HttpDownloader::get() and copy() answer with one.

Two gaps stay: decodeJson() reaches Composer\Json\JsonFile, which a guard
shadows, and Composer answers a curl request with the CurlResponse subclass
where this port flattens the value into a Response.

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

1 files changed, 22 insertions, 6 deletions

diff --git a/crates/shirabe/src/plugin/php_plugin_proxy.rs b/crates/shirabe/src/plugin/php_plugin_proxy.rs
index 491a320c..c966897b 100644
--- a/crates/shirabe/src/plugin/php_plugin_proxy.rs
+++ b/crates/shirabe/src/plugin/php_plugin_proxy.rs
@@ -21,7 +21,7 @@ use crate::package::{DisplayMode, PackageInterfaceHandle};
 use crate::plugin::capability::{Capability, CommandProvider};
 use crate::plugin::capable::Capable;
 use crate::plugin::php_plugin_value::{
-    date_time_from_wire, date_time_to_wire, link_from_wire, link_to_wire,
+    date_time_from_wire, date_time_to_wire, link_from_wire, link_to_wire, response_to_wire,
 };
 use crate::plugin::plugin_interface::PluginInterface;
 use crate::repository::{
@@ -1177,11 +1177,27 @@ fn dispatch_http_downloader_method(
             downloader.borrow_mut().set_options(options);
             Ok(PluginValue::Null)
         }
-        // TODO(plugin): a `Composer\Util\Http\Response` has no representation on the wire, so
-        // the two synchronous request methods have nothing to answer with.
-        "get" | "copy" => Err(runtime_throw(format!(
-            "Shirabe does not support HttpDownloader::{method_name}() from a plugin yet"
-        ))),
+        "get" => {
+            let url = arg::<String>(method_name, args, 0)?;
+            let options =
+                arg_or::<IndexMap<String, PhpMixed>>(method_name, args, 1, IndexMap::new())?;
+            let response = downloader
+                .borrow()
+                .get(&url, options)
+                .map_err(|error| error_throw("get failed", &error))?;
+            Ok(response_to_wire(&response))
+        }
+        "copy" => {
+            let url = arg::<String>(method_name, args, 0)?;
+            let to = arg::<String>(method_name, args, 1)?;
+            let options =
+                arg_or::<IndexMap<String, PhpMixed>>(method_name, args, 2, IndexMap::new())?;
+            let response = downloader
+                .borrow()
+                .copy(&url, &to, options)
+                .map_err(|error| error_throw("copy failed", &error))?;
+            Ok(response_to_wire(&response))
+        }
         // TODO(plugin,async): the async surface resolves its promises with a Response the wire
         // cannot carry, and driving it needs a promise representation that crosses the boundary
         // unresolved. Neither exists yet.