Function build_aws_config

pub async fn build_aws_config(
    profile: Option<String>,
    region: String,
) -> Result<SdkConfig>

Builds and returns an AWS SDK configuration based on the following priority:

1. Specified AWS profile (if provided)
2. AWS environment variables (if available)
3. Interactive SSO login (if user confirms)

This function can be reused to create any AWS service client.