fix(http): avoid nested tokio runtime panic in download path

The CurlDownloader owned a tokio runtime and block_on'd reqwest from its
sync tick(), while the repository/installer/downloader sync bridges each
created another Runtime and block_on'd async fns that reach that leaf.
Driving one Runtime::block_on from within another panics with "Cannot
start a runtime from within a runtime", hit by `require` when fetching
p2 metadata.

Switch CurlDownloader to a blocking reqwest client (its own internal
thread, never nested) and replace the per-call Runtime::new().block_on
bridges with a no-reactor sync_executor::block_on helper. No awaited
future parks on a reactor once the only async I/O is blocking, so the
helper can be nested freely.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

1 files changed, 12 insertions, 15 deletions

diff --git a/crates/shirabe/src/downloader/file_downloader.rs b/crates/shirabe/src/downloader/file_downloader.rs
index d3e1f6c..a6334fb 100644
--- a/crates/shirabe/src/downloader/file_downloader.rs
+++ b/crates/shirabe/src/downloader/file_downloader.rs
@@ -23,6 +23,7 @@ use crate::util::Platform;
 use crate::util::ProcessExecutor;
 use crate::util::Silencer;
 use crate::util::Url as UrlUtil;
+use crate::util::sync_executor;
 use anyhow::Result;
 use indexmap::IndexMap;
 use shirabe_php_shim::{
@@ -629,21 +630,17 @@ impl ChangeReportInterface for FileDownloader {
                     .remove_directory(format!("{}_compare", target_dir))?;
             }
 
-            tokio::runtime::Runtime::new()
-                .unwrap()
-                .block_on(self.download(
-                    package.clone(),
-                    &format!("{}_compare", target_dir),
-                    None,
-                    false,
-                ))?;
-            tokio::runtime::Runtime::new()
-                .unwrap()
-                .block_on(self.install(
-                    package.clone(),
-                    &format!("{}_compare", target_dir),
-                    false,
-                ))?;
+            sync_executor::block_on(self.download(
+                package.clone(),
+                &format!("{}_compare", target_dir),
+                None,
+                false,
+            ))?;
+            sync_executor::block_on(self.install(
+                package.clone(),
+                &format!("{}_compare", target_dir),
+                false,
+            ))?;
 
             let mut comparer = Comparer::new();
             comparer.set_source(format!("{}_compare", target_dir));