## 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
1ee8f49175