Fix: add chat_template required for OpenAI-compatible chat/completions

tokenizer_config.json

@@ -234,5 +234,6 @@
   "pad_token": "<|endoftext|>",
   "split_special_tokens": false,
   "tokenizer_class": "Qwen2Tokenizer",
-  "unk_token": null
+  "unk_token": null,
+  "chat_template": "{% if messages[0]['role'] == 'system' %}{% set system_message = messages[0]['content'] %}{% set loop_messages = messages[1:] %}{% else %}{% set system_message = '' %}{% set loop_messages = messages %}{% endif %}{% if system_message != '' %}<|im_start|>system\n{{ system_message }}<|im_end|>\n{% endif %}{% for message in loop_messages %}<|im_start|>{{ message['role'] }}\n{{ message['content'] }}<|im_end|>\n{% endfor %}{% if add_generation_prompt %}<|im_start|>assistant\n{% endif %}"
 }