chore: upgrade Qwen model default from 0.5B to 1.5B Instruct

webapp/tipitaka-api/app/services/query_transform_service.py

@@ -25,7 +25,7 @@ class QueryTransformService:
     _model = None
 
     @classmethod
-    def preload(cls, model_id: str = "Qwen/Qwen2.5-0.5B-Instruct"):
+    def preload(cls, model_id: str = "Qwen/Qwen2.5-1.5B-Instruct"):
         """Preload the model and tokenizer into memory if not already done."""
         if cls._model is not None and cls._tokenizer is not None:
             return
@@ -67,7 +67,7 @@ class QueryTransformService:
         self.runtime = os.getenv("QWEN_RUNTIME", "transformers")
         self.ollama_url = os.getenv("QWEN_OLLAMA_URL", "http://localhost:11434")
         self.ollama_model = os.getenv("QWEN_OLLAMA_MODEL", "qwen3.5:0.8b")
-        self.model_id = os.getenv("QWEN_MODEL_ID", "Qwen/Qwen2.5-0.5B-Instruct")
+        self.model_id = os.getenv("QWEN_MODEL_ID", "Qwen/Qwen2.5-1.5B-Instruct")
 
     def _normalize_key(self, query: str) -> str:
         # 1. ปรับรูปอักขระภาษาไทย (NFC) และแปลงเป็นตัวพิมพ์เล็ก