fix(audio): handle voice message failures gracefully

- Send user feedback when voice/audio download fails instead of silent failure
- Send graceful message when audio transcription is not configured instead of empty text which crashes API

src/channels/telegram/adapter.ts

@@ -300,6 +300,7 @@ export class TelegramAdapter implements ChannelAdapter {
       const fileData = await this.downloadFileToBase64(voice.file_id);
       if (!fileData) {
         console.error(`Failed to download voice message ${voice.file_id}`);
+        await ctx.reply('Sorry, I couldn\'t download your voice message. Please try again.', { reply_parameters: { message_id: ctx.message.message_id } });
         return;
       }
 
@@ -337,6 +338,7 @@ export class TelegramAdapter implements ChannelAdapter {
       const fileData = await this.downloadFileToBase64(audio.file_id);
       if (!fileData) {
         console.error(`Failed to download audio message ${audio.file_id}`);
+        await ctx.reply('Sorry, I couldn\'t download your audio file. Please try again.', { reply_parameters: { message_id: ctx.message.message_id } });
         return;
       }
 

src/daemon/routing.ts

@@ -254,6 +254,9 @@ export function createMessageRouter(deps: {
             const transcript = await transcribeAudio(att, audioConfig);
             messageText = `[Voice message]: ${transcript}\n\n${messageText}`;
           }
+        } else {
+          // No transcription endpoint configured — inform the user gracefully
+          messageText = `[Voice message received but audio transcription is not configured. Please configure the audio section in config.yaml to enable voice message support.]`;
         }
         // Remove audio attachments so buildUserMessage doesn't create audio content parts
         attachments = (msg.attachments ?? []).filter((a: Attachment) => !isSupportedAudio(a));