Codex client does not support openai/form requests from Sites design picker

Problem

In the Codex desktop client, the bundled Sites integration attempts to open the visual site-design picker, but the tool call fails because the client does not support openai/form requests.

Error shown

tool call error: tool call failed for `sites-design-picker/choose_site_design`

Caused by:
  Mcp error: -32602: The MCP client does not support openai/form requests.

Context from the UI

• Codex Desktop on macOS
• Flow: Sites integration creates an HTML preview (option-3.html), runs render-html-previews.sh, then shows Choose site design
• Clicking / invoking Choose site design triggers the error above
• The assistant then falls back to choosing a design itself instead of letting the user use the visual comparison form

Expected behavior

The Codex client should either:

1. support openai/form requests for MCP tools like sites-design-picker/choose_site_design, or
2. provide a graceful fallback UI / compatibility path so the Sites design picker can still work.

Why this matters

The visual comparison form is central to choosing between generated site designs. Without it, the user loses the intended review/selection step and the agent has to guess the best option.