core: let steer interrupt wait_agent

[jif-oai]

Why

wait_agent can block for a long timeout while waiting for sub-agent mailbox activity. Although same-turn user steer is accepted during that tool call, the input remains pending until the wait returns, so an explicit request to change direction can appear unresponsive.

What changed

• Notify active wait_agent calls when user input is steered into the current turn.
• Check for already-pending steer input when subscribing so input that races with tool startup is not missed.
• Distinguish mailbox activity, steered input, and timeout outcomes, returning Wait interrupted by new input. for the steer path.
• Update the wait_agent tool description to document the early-return behavior.

Testing

• just test -p codex-core input_queue_
• just test -p codex-core wait_agent

The coverage includes steer notification before and after subscription, plus an end-to-end test that verifies the interrupted wait result and steered user input are both included exactly once in the follow-up model request.

[jif-oai]

@codex review

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. Breezy!

Reviewed commit:6533d7582d

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Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[jif-oai]

@codex review

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. 🎉

Reviewed commit:e32b832c92

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".