Widen the exception guard from OSError to Exception (re-raising
KeyboardInterrupt/EOFError first) so any prompt_toolkit runtime
failure degrades to input() — matching the established pattern in
masked_secret_prompt. ValueError and RuntimeError can arise from
exotic stream wrappers or event-loop issues with the same root cause:
prompt_toolkit cannot attach stdin on the terminal.
Add test_line_input_falls_back_to_input_on_any_prompt_toolkit_failure
covering the ValueError case.
line_input() only guarded against a missing prompt_toolkit (ImportError),
not against prompt_toolkit failing at runtime. On some terminals isatty()
returns True but the asyncio event-loop selector rejects registering stdin
(macOS kqueue raises OSError EINVAL / 'Invalid argument' for fd 0), so
prompt_toolkit's Application.run() crashes while attaching its input.
This aborted 'hermes setup' at the first plain text prompt. Telegram hit it
first because its automatic/manual selection uses prompt() rather than the
curses-based prompt_choice() the other platforms use, but every text prompt
shared the same failure.
Catch OSError from the prompt_toolkit path and fall back to the built-in
input() reader, which needs no selector and works in cooked mode. The
prompt_toolkit raw-mode context manager restores terminal state on the way
out, so the fallback reads cleanly.
Widens #90327's line_input() to the whole bug class: all 46 bare input()
free-text prompt sites across the setup wizards (model_setup_flows, setup,
config, gateway, auth, auth_commands, plugins_cmd, skills_hub, bundles,
setup_whatsapp_cloud, main) now route through line_input(), and the shared
cli_output.prompt() / setup.prompt() helpers do too — so every CLI wizard
gets cursor editing, not just the custom model prompt.
Redirected stdin and missing prompt_toolkit keep builtin input() behavior.
E2E: real PTY with raw escape bytes through line_input, cli_output.prompt,
and setup.prompt (arrows + Ctrl+A/E edit correctly); redirected-stdin
fallback verified.
