Feature Request: Add HTTPS-only Transport Option

Summary

Please add a way to force Codex to use HTTPS transport directly without attempting WebSocket connections first.

Problem

In some network environments (corporate proxies, Clash/Mihomo, VPNs, restricted networks), WebSocket connections frequently fail or time out.

Current behavior:

1. Codex attempts WebSocket transport.
2. Connection times out.
3. Codex retries multiple times.
4. Codex falls back to HTTPS.
5. Request finally succeeds.

Example log:

Falling back from WebSockets to HTTPS transport
Reconnecting... 4/5
Request timed out

Although HTTPS works correctly, users must wait through several failed WebSocket attempts before the request is processed.

Expected Behavior

Allow users to explicitly disable WebSocket transport.

Examples:

codex --transport=https

or

transport = "https"

or

supports_websockets = false

Benefits

• Faster startup in restricted network environments.
• Better compatibility with enterprise proxies.
• Reduced connection delays.
• More predictable behavior.

Environment

• Codex CLI: v0.139.0
• Platform: macOS
• Network: Proxy / Clash environment
• HTTPS works correctly after WebSocket fallback.