fix(cli): bridge question forms over ACP

[a12233]

Summary

• advertise the private OpenCode ACP elicitation capability during initialization
• translate question-backed form.created events into session/elicitation requests
• map accepted single-select, multiselect, and custom answers back through the V2 form reply API
• cancel question forms when elicitation is unsupported or declined

Root cause

The V2 question tool emits form.created, but the ACP bridge treated all forms as unsupported and cancelled them. ACP clients therefore saw the question tool fail with The user dismissed this question and never received an elicitation request.

Testing

• bun test test/acp/question.test.ts test/acp/event-behavior.test.ts
• bun typecheck in packages/cli
• repository pre-push bun turbo typecheck --concurrency=3 (33 packages)
• manual ACP subprocess: observed session/elicitation, accepted q0: "Alpha", question tool completed, prompt returned end_turn

[github-actions]

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[github-actions]

Thanks for your contribution!

This PR doesn't have a linked issue. All PRs must reference an existing issue.

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[github-actions]

The following comment was made by an LLM, it may be inaccurate:

Based on my search, I found one related PR that may be worth checking:

Related PR:

• refactor(core): make form ledger global #46704 - refactor(core): make form ledger global - This touches form handling which is related to the form reply API changes in the current PR.

Note: I also found historical references (#42158, #20017) but these are older and likely already merged/closed.

The current PR (#46845) is the only open PR directly addressing the ACP question form bridging. No duplicate open PRs found for this specific feature.

[a12233]

Closing this upstream PR; this integration is specific to a personal fork consumer and will be tracked in the fork instead.