WebSocket connections fail behind Fence sandbox (ignore HTTPS_PROXY)

Summary

When running Command Code inside popular sandbox tool Fence (https://github.com/fencesandbox/fence) (Linux sandbox using bwrap --unshare-net), all WebSocket connections time out. Fence routes network traffic through an HTTP proxy (HTTPS_PROXY=http://127.0.0.1:3128) since direct TCP is blocked by the network namespace.

curl, fetch, and HTTP requests work correctly. However, new WebSocket(url) (used in buildSandboxStreamUrl / defaultCreateSandboxStreamSocket) ignores proxy env vars and attempts a direct TCP connection, which is blocked by the sandbox.

The codebase already has detectProxyFromEnv(). Maybe use ws package with https-proxy-agent for WebSocket connections when a proxy is detected, instead of the built-in WebSocket

Expected Behavior

CommandCode working inside Fence sandboxing

Actual Behavior

Connection issues with Fence. Can't use CommandCode with it.

Steps to reproduce the issue

1. Install and configure Fence ( https://github.com/fencesandbox/fence )
2. Run CommandCode with "fence cmd"

Command Code Version

1.10.0

Operating System

Linux

Terminal/IDE

JetBrains-JediTerm

Shell

bwrap

Session file (optional)

No response

Fix prompt (optional)

No response

Additional context

No response

まず buildSandboxStreamUrl と defaultCreateSandboxStreamSocket を追跡し、次に既存の HTTP リクエストで detectProxyFromEnv がどのように使用されているかを確認します。Fence sandbox の失敗を再現し、設定された HTTPS_PROXY 経由で WebSocket 接続が成功することを、直接接続を壊さずに検証します。