Improve AWS credential validation and use AWS_DEFAULT_REGION

llm.py

@@ -27,19 +27,22 @@ def get_bedrock_client():
     """Get or create the Bedrock runtime client with proper error handling."""
     global _bedrock_runtime
     if _bedrock_runtime is None:
-        aws_access_key = os.getenv("AWS_ACCESS_KEY_ID")
-        aws_secret_key = os.getenv("AWS_SECRET_ACCESS_KEY")
+        aws_access_key = os.getenv("AWS_ACCESS_KEY_ID", "").strip()
+        aws_secret_key = os.getenv("AWS_SECRET_ACCESS_KEY", "").strip()
+        aws_region = os.getenv("AWS_DEFAULT_REGION", "us-east-1").strip()
         
         if not aws_access_key or not aws_secret_key:
             raise ValueError(
                 "AWS credentials not found. Please set AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY "
-                "as secrets in Hugging Face Spaces settings."
+                "as secrets in Hugging Face Spaces settings. "
+                f"Current values: AWS_ACCESS_KEY_ID={'***' if aws_access_key else 'EMPTY'}, "
+                f"AWS_SECRET_ACCESS_KEY={'***' if aws_secret_key else 'EMPTY'}"
             )
         
         try:
             _bedrock_runtime = boto3.client(
                 "bedrock-runtime", 
-                region_name="us-east-1",
+                region_name=aws_region,
                 aws_access_key_id=aws_access_key,
                 aws_secret_access_key=aws_secret_key
             )