fix: keep dave chat responsive on llm failures

test/telegram-chat.test.mjs

@@ -117,6 +117,41 @@ test('Telegram transport routes authorized free text as plain-text AI reply', as
   assert.equal(sent.body.reply_to_message_id, 11);
 });
 
+test('Telegram AI handler failures return short DAVE fallback messages', async () => {
+  const alerter = new TelegramAlerter({ botToken: 'test-token', chatId: '42' });
+  const requests = [];
+  alerter.onMessage(async () => {
+    throw new Error('The operation was aborted due to timeout');
+  });
+
+  const originalFetch = globalThis.fetch;
+  globalThis.fetch = async (url, options = {}) => {
+    requests.push({ url, body: options.body ? JSON.parse(options.body) : null });
+    if (url.includes('/getUpdates')) {
+      return {
+        ok: true,
+        json: async () => ({
+          ok: true,
+          result: [{ update_id: 1, message: { message_id: 10, text: 'Noch da?', chat: { id: 42 } } }],
+        }),
+      };
+    }
+    return { ok: true, json: async () => ({ ok: true, result: { message_id: requests.length } }) };
+  };
+
+  try {
+    await alerter._pollUpdates();
+  } finally {
+    globalThis.fetch = originalFetch;
+  }
+
+  const sent = requests.filter(request => request.url.includes('/sendMessage'));
+  assert.equal(sent.length, 2);
+  assert.match(sent[0].body.text, /Dave bekommt gerade keine stabile Antwort/);
+  assert.doesNotMatch(sent.map(item => item.body.text).join('\n'), /AI chat failed|Please try again/i);
+  assert.equal(sent[0].body.reply_to_message_id, 10);
+});
+
 test('Telegram conversation delivery strips visible markdown and splits large AI replies', async () => {
   const alerter = new TelegramAlerter({ botToken: 'test-token', chatId: '42' });
   const requests = [];
@@ -209,8 +244,8 @@ test('Telegram tiered fallback alert is sent as conversational DAVE messages', a
 
   const texts = requests.filter(request => request.url.includes('/sendMessage')).map(request => request.body.text);
   assert.ok(texts.length >= 2);
-  assert.match(texts[0], /^\[DAVE \/\/ HINWEIS\]/);
-  assert.doesNotMatch(texts.join('\n'), /CRUCIX ROUTINE|Confidence:|Direction:|Cross-correlation:|Werkzeuge|Tools used/);
+  assert.match(texts[0], /^Kurzer Hinweis:/);
+  assert.doesNotMatch(texts.join('\n'), /\[DAVE \/\/|CRUCIX ROUTINE|Confidence:|Direction:|Cross-correlation:|Werkzeuge|Tools used/);
   for (const text of texts) assert.ok(text.length <= 380, `alert chunk too long: ${text.length}`);
 });