Let admins hear a voice sample before picking it

The Speech section of every model settings form now has "Hear a
sample", which streams a short sentence (AppData.VoicePreviewText) in
the form's model and voice before they're saved, through
GET api/admin/harness/preview-voice (super admins and admins, that
model only via grabModelCandidate). pickVoice is shared with
speakText, and explainAudioError reads why a streamed player failed
for both read-aloud and the sample.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

AGENTS.md

@@ -93,7 +93,7 @@ Inspect live data with `bun llm-code-assistant/query-db.ts "<sql>"` - a read-onl
 - **Server:** `src/functions/backend/db/bots/` (`grab-bots`, `grab-bot-messages`, `grab-active-bot-task`, `grab-user-bot`, `create-bot`, `insert-user-message`). `api/admin/bots/send-message.ts` posts a user message to a bot the session user chats with (zod: `src/schemas/bot-schema.ts`), queues the bot's reply (`enqueueBotReply`) and wakes the queue (`src/bots-queue/wake-bots-queue.ts`; never import `src/bots-queue/index.ts` from a page or API route, it pulls the bunext runtime into the page bundles). `upload-attachment.ts` stores one file for the next message (private `media` row, paradigm `bot-attachment`, type from `attachmentFileKind`, documents get `text_content`, limits in `AppData.BotAttachment*`) and `send-message` takes their `media_ids` (checked to be the user's own by `grabAttachableMedia`), linked in `bot_message_media`; messages carry `attachments` (`BotMessageWithAttachments`). `mark-read.ts` clears a session's unread when a message arrives in the open conversation; `session-messages.ts` returns a session's latest messages, which the open conversation polls every `AppData.BotReplyCatchUpMs` while a reply is due (`use-reply-catch-up`), so a reply whose live push was missed (socket down) still lands without a reload (replayed as a `server:bot-message`, so the rail and unread take it too); `create-bot.ts` adds a worker (and puts it in a workspace when given one); `save-harness-settings.ts` saves a worker bot's models.
 - **Message rendering:** bot messages are markdown, rendered with `react-markdown` + `remark-gfm` (raw HTML never rendered) through the twui-based map in `[bot_id]/(data)/message-markdown-components.tsx` (`markdown-link`, `markdown-list`, `markdown-code-block` partials). User messages stay plain text.
 - **Attachments and thinking:** the composer uploads files as they're picked, pasted or dropped (`use-composer-attachments`), shows them as chips, and sends once none is still uploading; the thread shows images as thumbnails and other files as chips. Replies read the files of the last `BotReplyAttachmentMessages` messages with any (`load-attachment-parts.ts`: images and audio as parts, documents as their text up to `BotAttachmentMaxTextChars`, videos as a note); older ones are only named. Tasks don't get the files yet. While the user has the last word in a session (every user message queues a reply, so this needs no face and shows even while the bot works in another session) or the bot waits for a model (`BotWaitingStatusLine`) or a task for its computer (`BotComputerBusyStatusLine`), `BotThinkingRow` sits under the last message; while a task runs it reads "<name> is working…" with the task's latest step, and a reply working through tools shows its latest step under "is thinking…" (`use-reply-progress`). A coordinator with no workers gets `CoordinatorSoloNote` instead of `CoordinatorReplyNote`, so it never claims to have handed work to a worker. Live notices come from the process that ran the job at once, and from every other process through the live relay.
-- **Voice:** the composer's mic (`(partials)/composer-voice-button.tsx`, `use-voice-recorder`, shown once the browser can record, disabled with a note while transcription has no model to run on for the bot there, `bot_voice` page prop, from `resolveHarnessCandidates`) dictates: the recording goes to `api/admin/bots/transcribe.ts` (`transcribeAudio` with the bot's models, after `grabUserConversation`) and the text lands in the input at the cursor, to edit and send; Escape cancels, `AppData.ComposerVoiceMaxMs` stops it. Each bot message has a play button (disabled with a note while speech has no model) (`speak-message-button.tsx`, one player per conversation via `SpeakMessageContext` / `use-speak-message`) that plays `GET api/admin/bots/speak-message.ts?message_id=` straight in an `<audio>` (`speakText` streamed through as the provider makes it, so it starts in a couple of seconds; a failure answers in JSON, which the hook fetches again to show; only the user's own sessions, `grabSpeakableMessage`; text from `speechText`, cut at `AppData.SpeechMaxChars`). Neither recordings nor audio are stored. Harness errors (`HarnessError`, safe to show) come back as the buttons' titles.
+- **Voice:** the composer's mic (`(partials)/composer-voice-button.tsx`, `use-voice-recorder`, shown once the browser can record, disabled with a note while transcription has no model to run on for the bot there, `bot_voice` page prop, from `resolveHarnessCandidates`) dictates: the recording goes to `api/admin/bots/transcribe.ts` (`transcribeAudio` with the bot's models, after `grabUserConversation`) and the text lands in the input at the cursor, to edit and send; Escape cancels, `AppData.ComposerVoiceMaxMs` stops it. Each bot message has a play button (disabled with a note while speech has no model) (`speak-message-button.tsx`, one player per conversation via `SpeakMessageContext` / `use-speak-message`) that plays `GET api/admin/bots/speak-message.ts?message_id=` straight in an `<audio>` (`speakText` streamed through as the provider makes it, so it starts in a couple of seconds; a failure answers in JSON, which the hook fetches again to show; only the user's own sessions, `grabSpeakableMessage`; text from `speechText`, cut at `AppData.SpeechMaxChars`). Under Speech, every model settings form has "Hear a sample" (`settings/models/(partials)/harness-voice-preview.tsx`), which plays `AppData.VoicePreviewText` in the form's model and voice before they're saved (`GET api/admin/harness/preview-voice`, super admins and admins, that model only via `grabModelCandidate`, streamed). Neither recordings nor audio are stored. Harness errors (`HarnessError`, safe to show) come back as the buttons' titles.
 - **Pictures:** a bot or workspace can have a picture (`image_media_id`, a private `media` row, paradigm `bot-image`/`workspace-image`), set or removed through `api/admin/set-profile-image.ts` (`setProfileImage`, the old one deleted; served at `profileImageUrls`). `BotAvatar` shows a bot's picture as a rounded square, else its stone; its hue still applies. `WorkspaceAvatar` shows a workspace's, else the workspace icon. A bot is edited from the header avatar (`(partials)/bot-profile-modal.tsx`, the same `BotForm` as adding one, `api/admin/bots/update-bot.ts`; the coordinator keeps its name and stays hue-less).
 - **Avatars:** `BotStone` (`src/components/general/bot-stone.tsx`) renders the stone inline from `src/data/stone-geometry.ts`, hue as a fill token, face (`idle|working|done|asleep|needs-you`) drawn as eyes. The coordinator is hue-less (ink body, paper eyes; inverts in dark). Never put a stone in a circle/badge or add outline/shadow. Wordmark is vector (`Wordmark`, `src/data/wordmark-paths.ts`), never live text.
 - **Copy helpers:** `src/utils/crew-status.ts` (`3 working · 1 needs you`, "Three bots are working. One needs you."), `src/utils/relative-time.ts` (relative timestamps only).