docs: add readme for example

Author: sgtoj

examples/complete/README.md

@@ -1,3 +1,34 @@
 # Terraform Module Example
 
-## Complete
+## Complete Example
+
+This directory provides a complete example of how to use the CloudFront
+Middleware-at-Edge module. This example deploys a simple static website using
+CloudFront and S3, with a Cognito User Pool for authentication and
+authorization. Lambda@Edge functions are deployed for URL rewriting and managing
+authentication.
+
+### Usage
+
+To run this example, provide your own values for the following variables in a
+`terraform.tfvars` file:
+
+```hcl
+domain_name                  = "example.com"
+domain_parent_hosted_zone_id = "Z0123456789ABCDEFG"
+```
+
+### Inputs
+
+| Name                         | Description                                      |  Type  | Default | Required |
+|------------------------------|--------------------------------------------------|:------:|:-------:|:--------:|
+| domain_name                  | The domain name for the CloudFront distribution. | string |   n/a   |   yes    |
+| domain_parent_hosted_zone_id | The ID of the parent hosted zone in Route 53.    | string |   n/a   |   yes    |
+
+### Outputs
+
+| Name                   | Description                                     |
+|------------------------|-------------------------------------------------|
+| website_domain_name    | The domain name of the website.                 |
+| website_cf_domain_name | The domain name of the CloudFront distribution. |
+| test_user_credentials  | The credentials of the test user.               |