[chrisnestrud]

Problem

With tui: false, IOProxy.get_input delegated straight to the base
InputOutput terminal prompt and never drained the per-coder queue that
IOProxy.__init__ registers. So input pushed via queues.push_coder_input(...)
from the WebSocket server (cecli/helpers/server/ws_server.py), the ACP adapter
(cecli/helpers/server/acp/protocol.py), or AgentService.wake_primary
(cecli/helpers/agents/service.py) was silently dropped. confirm_ask had the
same gap, dropping queued confirmations. tui: true was unaffected because
TextualInputOutput.get_input drains the queues.

This also contradicted wake_primary's docstring, which assumes the idle primary
blocks in wait_for_input().

Fix

Non-TUI IOProxy.get_input now:

1. Sweeps this coder's queue first (non-blocking).
2. When nothing is waiting and a cancellable prompt session is present, races the
   terminal read against the per-coder queue wake, so a push is delivered even
   while the prompt is open.
3. Falls back to a plain blocking read for the InterruptibleInput/input()
   path, which cannot be cancelled (marked with a ponytail: note naming the
   ceiling).

Confirmations take the same route and reuse the TUI payload mapping
(never/tweak/all/skip/bool) so both modes agree.

Why this shape

The wake event in cecli/helpers/queues.py is global, so the race loop
re-checks this coder's own queue after each wake instead of trusting a single
signal. A payload meant for a different reader is put back so its own waiter
still consumes it.

Tests

tests/subagents/test_io_proxy.py: queued text returns (text, uuid) and logs
user_input; a push is delivered while the terminal prompt is open; a
confirmation is left for confirm_ask by get_input; queued true/false
confirmations return the expected values.

Verified offline: tests/subagents/test_io_proxy.py 16 passed,
tests/unit/test_queues.py 15 passed; black (--line-length 100 --preview),
isort, pycodestyle, pyflakes, codespell clean; interactive tui=false re-prompt
loop unchanged (no regression).

Related

Documentation follow-up for this change: #698 (documents the non-TUI
input contract; merge after this PR).