feat(telegram-tts): add auto-TTS hook and provider switching

- Integrate message_sending hook into Telegram delivery path
- Send text first, then audio as voice message after
- Add /tts_provider command to switch between OpenAI and ElevenLabs
- Implement automatic fallback when primary provider fails
- Use gpt-4o-mini-tts as default OpenAI model
- Add hook integration to route-reply.ts for other channels

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/telegram/bot/delivery.ts

@@ -14,6 +14,7 @@ import { mediaKindFromMime } from "../../media/constants.js";
 import { fetchRemoteMedia } from "../../media/fetch.js";
 import { isGifMedia } from "../../media/mime.js";
 import { saveMediaBuffer } from "../../media/store.js";
+import { getGlobalHookRunner } from "../../plugins/hook-runner-global.js";
 import type { RuntimeEnv } from "../../runtime.js";
 import { loadWebMedia } from "../../web/media.js";
 import { resolveTelegramVoiceSend } from "../voice.js";
@@ -39,6 +40,45 @@ export async function deliverReplies(params: {
   const threadParams = buildTelegramThreadParams(messageThreadId);
   let hasReplied = false;
   for (const reply of replies) {
+    // Track if hook wants to send audio after text
+    let audioToSendAfter: string | undefined;
+
+    // Run message_sending hook (allows plugins like TTS to generate audio)
+    const hookRunner = getGlobalHookRunner();
+    if (hookRunner && reply?.text?.trim()) {
+      try {
+        const hookResult = await hookRunner.runMessageSending(
+          {
+            to: chatId,
+            content: reply.text,
+            metadata: { channel: "telegram", threadId: messageThreadId },
+          },
+          {
+            channelId: "telegram",
+            accountId: undefined,
+            conversationId: chatId,
+          },
+        );
+
+        // Check if hook wants to cancel the message
+        if (hookResult?.cancel) {
+          continue; // Skip this reply
+        }
+
+        // Check if hook returned a MEDIA directive (TTS audio)
+        if (hookResult?.content !== undefined) {
+          const mediaMatch = hookResult.content.match(/^MEDIA:(.+)$/m);
+          if (mediaMatch) {
+            // Save audio path to send AFTER the text message
+            audioToSendAfter = mediaMatch[1].trim();
+          }
+        }
+      } catch (err) {
+        // Hook errors shouldn't block message sending
+        logVerbose(`[telegram delivery] hook error: ${String(err)}`);
+      }
+    }
+
     const hasMedia = Boolean(reply?.mediaUrl) || (reply?.mediaUrls?.length ?? 0) > 0;
     if (!reply?.text && !hasMedia) {
       if (reply?.audioAsVoice) {
@@ -70,6 +110,25 @@ export async function deliverReplies(params: {
           hasReplied = true;
         }
       }
+
+      // Send TTS audio after text (if hook generated one)
+      if (audioToSendAfter) {
+        try {
+          const audioMedia = await loadWebMedia(audioToSendAfter);
+          const audioFile = new InputFile(audioMedia.buffer, "voice.mp3");
+          // Switch typing indicator to record_voice before sending
+          await params.onVoiceRecording?.();
+          const audioParams: Record<string, unknown> = {};
+          if (threadParams) {
+            audioParams.message_thread_id = threadParams.message_thread_id;
+          }
+          await bot.api.sendVoice(chatId, audioFile, audioParams);
+          logVerbose(`[telegram delivery] TTS audio sent: ${audioToSendAfter}`);
+        } catch (err) {
+          logVerbose(`[telegram delivery] TTS audio send failed: ${String(err)}`);
+        }
+      }
+
       continue;
     }
     // media with optional caption on first item