## Why
`codex-app-server-test-client` previously treated
`item/tool/requestUserInput` as an unsupported server request and
terminated the connection. That made it impossible to use the client for
end-to-end testing of interactive turns: an operator could observe the
request, but could not answer it and confirm that the same turn resumed.
## What changed
- Handle `ToolRequestUserInput` server requests in the test client's
central request dispatcher.
- Render numbered terminal choices, accept exact option labels, support
free-form `Other` and text-only questions, and collect multiple answers.
- Send a protocol-native `ToolRequestUserInputResponse` and continue
streaming the active turn.
- Fail clearly when interactive input is requested without a terminal.
- Document the interactive behavior and add focused tests for option
selection, free-form answers, multiple questions, and invalid-selection
retries.
## Testing
- `just test -p codex-app-server-test-client`
- `just bazel-lock-check`
- Manually exercised the app-server flow, selected `TUI`, observed
`serverRequest/resolved`, and verified that the same turn completed with
the selected answer.
Celia Chen