Update embedding model to BAAI/bge-large-en-v1.5 for better document retrieval performance

config.py

@@ -33,7 +33,7 @@ VOICE_LANGUAGE = os.environ.get("VOICE_LANGUAGE", "en-US")
 DEFAULT_VOICE_SPEED = float(os.environ.get("DEFAULT_VOICE_SPEED", "1.0"))
 
 # Embedding Model Configuration
-EMBEDDING_MODEL_NAME = os.environ.get("EMBEDDING_MODEL_NAME", "sentence-transformers/all-MiniLM-L6-v2")
+EMBEDDING_MODEL_NAME = os.environ.get("EMBEDDING_MODEL_NAME", "BAAI/bge-large-en-v1.5")  # Updated to use BGE model
 EMBEDDING_SIZE = 768
 
 # Text Processing Configuration