fix(telegram): use word-boundary matching for bot mention detection (#12545)

gateway/platforms/telegram.py

@@ -2264,8 +2264,9 @@ class TelegramAdapter(BasePlatformAdapter):
             yield getattr(message, "caption", None) or "", getattr(message, "caption_entities", None) or []
 
         for source_text, entities in _iter_sources():
-            if bot_username and f"@{bot_username}" in source_text.lower():
-                return True
+            if bot_username:
+                if re.search(rf'(?<!\w)@{re.escape(bot_username)}(?!\w)', source_text, re.IGNORECASE):
+                    return True
             for entity in entities:
                 entity_type = str(getattr(entity, "type", "")).split(".")[-1].lower()
                 if entity_type == "mention" and bot_username: