Route exec-server HTTP through configured proxy policy (#35023)

## Why

Delegated HTTP requests need to honor the same outbound proxy policy as the
Codex process that starts the exec server.

## What changed

- Pass the configured `HttpClientFactory` through local and remote exec-server
  startup and use route-aware client pools for delegated HTTP and local MCP
  requests.
- Preserve per-request timeouts and follow-or-stop redirect behavior while
  keeping request URLs and sensitive response headers out of diagnostics.

## Testing

- Cover configured system-proxy routing across the exec-server transport.
- Cover both redirect policies and verify that success and failure logs do not
  expose request or response secrets.

GitOrigin-RevId: 4af6aec1d265c4db62dfcb6e1fb076fb31736137

codex-rs/exec-server/src/server/transport.rs

@@ -12,6 +12,7 @@ use axum::response::IntoResponse;
 use axum::response::Response;
 use axum::routing::any;
 use axum::routing::get;
+use codex_http_client::HttpClientFactory;
 use std::io::Write as _;
 use std::net::SocketAddr;
 use tokio::io;
@@ -83,20 +84,32 @@ pub(crate) async fn run_transport(
     listen_url: &str,
     runtime_paths: ExecServerRuntimePaths,
     telemetry: ExecServerTelemetry,
+    http_client_factory: HttpClientFactory,
 ) -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
     match parse_listen_url(listen_url)? {
         ExecServerListenTransport::WebSocket(bind_address) => {
-            run_websocket_listener(bind_address, runtime_paths, telemetry).await
+            run_websocket_listener(bind_address, runtime_paths, telemetry, http_client_factory)
+                .await
+        }
+        ExecServerListenTransport::Stdio => {
+            run_stdio_connection(runtime_paths, telemetry, http_client_factory).await
         }
-        ExecServerListenTransport::Stdio => run_stdio_connection(runtime_paths, telemetry).await,
     }
 }
 
 async fn run_stdio_connection(
     runtime_paths: ExecServerRuntimePaths,
     telemetry: ExecServerTelemetry,
+    http_client_factory: HttpClientFactory,
 ) -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
-    run_stdio_connection_with_io(io::stdin(), io::stdout(), runtime_paths, telemetry).await
+    run_stdio_connection_with_io(
+        io::stdin(),
+        io::stdout(),
+        runtime_paths,
+        telemetry,
+        http_client_factory,
+    )
+    .await
 }
 
 async fn run_stdio_connection_with_io<R, W>(
@@ -104,12 +117,14 @@ async fn run_stdio_connection_with_io<R, W>(
     writer: W,
     runtime_paths: ExecServerRuntimePaths,
     telemetry: ExecServerTelemetry,
+    http_client_factory: HttpClientFactory,
 ) -> Result<(), Box<dyn std::error::Error + Send + Sync>>
 where
     R: AsyncRead + Unpin + Send + 'static,
     W: AsyncWrite + Unpin + Send + 'static,
 {
-    let processor = ConnectionProcessor::new_with_telemetry(runtime_paths, telemetry);
+    let processor =
+        ConnectionProcessor::new_with_telemetry(runtime_paths, telemetry, http_client_factory);
     tracing::info!("codex-exec-server listening on stdio");
     processor
         .run_connection(
@@ -126,10 +141,12 @@ async fn run_websocket_listener(
     bind_address: SocketAddr,
     runtime_paths: ExecServerRuntimePaths,
     telemetry: ExecServerTelemetry,
+    http_client_factory: HttpClientFactory,
 ) -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
     let listener = TcpListener::bind(bind_address).await?;
     let local_addr = listener.local_addr()?;
-    let processor = ConnectionProcessor::new_with_telemetry(runtime_paths, telemetry);
+    let processor =
+        ConnectionProcessor::new_with_telemetry(runtime_paths, telemetry, http_client_factory);
     info!("codex-exec-server listening on ws://{local_addr}");
     println!("ws://{local_addr}");
     std::io::stdout().flush()?;