Remote image URIs are forwarded to app-server and rejected

[ruixingshi]

Hi! The TypeScript adapter currently forwards HTTP/HTTPS image URIs directly to Codex app-server:

{
  "type": "image",
  "url": "https://example.com/image.png"
}

Codex app-server rejects this with:

remote image URLs are not supported; use an inline data URL instead

I think the existing Rust codex-acp adapter may be a useful reference here, since it uses inline Base64 image data instead of remote image URLs.

Tested with Codex CLI 0.144.4.

Detail refers to this issue: openai/codex#33788