feat: output the application integration URL

Add an `application_integration_url` output (the module previously had none) so
consumers can embed the AWS WAF JavaScript SDK from that URL to mint challenge
tokens in the browser. Additive; no behavior change.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: mrotondo

README.md

@@ -460,6 +460,12 @@ will be allowed through.
 | path       | The path to match.                                                                                                                       | `string` | n/a         | yes      |
 | constraint | The constraint to apply when matching the path. Supported values are `EXACTLY`, `STARTS_WITH`, `ENDS_WITH`, `CONTAINS`, `CONTAINS_WORD`. | `string` | `"EXACTLY"` | no       |
 
+## Outputs
+
+| Name                        | Description                                                                                        |
+|-----------------------------|----------------------------------------------------------------------------------------------------|
+| application_integration_url | URL for the AWS WAF application integration SDK (CAPTCHA/Challenge JavaScript API) for token minting. |
+
 [acm]: https://aws.amazon.com/certificate-manager/
 
 [acm-import]: https://docs.aws.amazon.com/acm/latest/userguide/import-certificate.html

outputs.tf

@@ -0,0 +1,8 @@
+output "application_integration_url" {
+  description = <<-EOT
+    URL for the AWS WAF application integration SDK (CAPTCHA/Challenge JavaScript
+    API). Embed the challenge.js or jsapi.js script from this URL to mint tokens
+    in the browser.
+    EOT
+  value       = aws_wafv2_web_acl.waf.application_integration_url
+}