feat(audio): add accept/discard buttons to audio recording

[alejandro-workpath]

Summary

• When recording audio, the single X button (which always sent the recording) is replaced with two distinct actions: checkmark (accept/send) and X (discard)
• Adds audio_discard socket event and @cl.on_audio_discard callback so backend apps can clean up resources when audio is discarded (e.g. close streaming transcription sessions)
• Backward-compatible: apps without on_audio_discard handler work unchanged

Why

Clicking X sends the audio instead of discarding it, which is confusing UX. There is no way to cancel a recording without sending it to the backend.

What was considered

• Buffer-then-decide: record locally, show accept/discard, only send on accept. Rejected because it breaks the real-time streaming architecture (chunks are sent as they're recorded).
• Chosen approach: keep real-time streaming, add audio_discard event so the backend knows to discard accumulated chunks and clean up. The frontend stops the recorder/player without emitting audio_end.

Test plan

• Start recording → click X (discard) → verify no on_audio_end fires, on_audio_discard fires instead
• Start recording → click checkmark (accept) → verify on_audio_end fires, transcription works
• Verify tooltips show "Discard recording" and "Send recording"
• App without on_audio_discard handler works without errors

Recording	Discard	Send

---

Summary by cubic

Add accept and discard controls to audio recording so users can cancel without sending. Adds audio_discard and the @cl.on_audio_discard hook so backends can clean up; apps without it keep working.

• New Features

  • Split actions into check (send) and X (discard) with clear tooltips; P hotkey accepts.
  • Discard emits audio_discard; stops local recorder/player and turns audio off without audio_end.
  • Added i18n keys for “Send recording” and “Discard recording” with native translations across all locales.

• Bug Fixes

  • Always reset audio state on discard: backend sets connection "off" in a finally block, and frontend always emits audio_discard even if local stop fails.
  • Restored inline comments in the VoiceButton hotkey guard for clarity.

^{Written for commit ee511a0. Summary will update on new commits.}

[cubic-dev-ai]

2 issues found across 8 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="backend/chainlit/socket.py">

<violation number="1" location="backend/chainlit/socket.py:474">
P2: `audio_discard` can skip emitting `audio_connection="off"` when `on_audio_discard()` raises, causing stale audio connection state.</violation>
</file>

<file name="libs/react-client/src/useAudio.ts">

<violation number="1" location="libs/react-client/src/useAudio.ts:33">
P2: Discard notification is skipped if local stop fails, so backend audio cleanup may never be triggered.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

10 issues found across 22 files (changes from recent commits).

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="backend/chainlit/translations/ko.json">

<violation number="1" location="backend/chainlit/translations/ko.json:86">
P2: Korean locale adds new audio action labels in English, causing mixed-language UI for `ko` users.</violation>
</file>

<file name="backend/chainlit/translations/ja.json">

<violation number="1" location="backend/chainlit/translations/ja.json:72">
P2: Japanese locale adds new speech action labels in English, causing mixed-language UI for `ja` users.</violation>
</file>

<file name="backend/chainlit/translations/it.json">

<violation number="1" location="backend/chainlit/translations/it.json:86">
P2: New Italian speech-action translations were added in English, causing mixed-language UI in the `it` locale.</violation>
</file>

<file name="backend/chainlit/translations/da-DK.json">

<violation number="1" location="backend/chainlit/translations/da-DK.json:85">
P2: Danish locale adds English strings for new audio actions, causing mixed-language UI in `da-DK`.</violation>
</file>

<file name="backend/chainlit/translations/fr-FR.json">

<violation number="1" location="backend/chainlit/translations/fr-FR.json:86">
P2: French locale adds new speech action labels in English, causing mixed-language UI for fr-FR users.</violation>
</file>

<file name="backend/chainlit/translations/pt-PT.json">

<violation number="1" location="backend/chainlit/translations/pt-PT.json:86">
P2: Portuguese locale includes untranslated English strings for new speech actions, causing mixed-language UI.</violation>
</file>

<file name="backend/chainlit/translations/es.json">

<violation number="1" location="backend/chainlit/translations/es.json:86">
P2: Spanish locale adds `chat.speech.accept` and `chat.speech.discard` in English, causing mixed-language UI in `es` translations.</violation>
</file>

<file name="backend/chainlit/translations/hi.json">

<violation number="1" location="backend/chainlit/translations/hi.json:72">
P2: New Hindi locale keys for audio actions are left in English, causing mixed-language UI in `hi` localization.</violation>
</file>

<file name="backend/chainlit/translations/zh-CN.json">

<violation number="1" location="backend/chainlit/translations/zh-CN.json:72">
P2: New zh-CN speech action labels are untranslated English strings, causing mixed-language UI for Chinese users.</violation>
</file>

<file name="backend/chainlit/translations/el-GR.json">

<violation number="1" location="backend/chainlit/translations/el-GR.json:86">
P2: New Greek locale entries for audio actions are untranslated English strings, causing mixed-language UI in `el-GR`.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[alejandro-workpath]

Hey guys, I would love to have this in production to improve some clients UX overall since the current setup is confusing for most of them. Can I ask for a review so I can refine if anything needs more work and merge it? @hayescode @asvishnyakov @sandangel Thank you so much!