docs(deploy): note CloudFormation teardown for CodeBuild deployments

The CodeBuild deploy path needs no local tooling, so 'cdk destroy' isn't readily available. Document 'aws cloudformation delete-stack --stack-name <stack_name_base>' as the teardown for that path in DEPLOYMENT.md (Option B + Cleanup) and scripts/README.md.

Author: razkenari

docs/DEPLOYMENT.md

@@ -302,7 +302,13 @@ cd infra-cdk
 cdk destroy --force
 ```
 
-If you deployed via CodeBuild (Option B), its build resources are already removed on success (or on the next successful run) — only the deployed FAST stack above needs tearing down.
+If you deployed via CodeBuild (Option B), its build resources are already removed on success (or on the next successful run) — only the deployed FAST stack above needs tearing down. If you don't have CDK installed locally (the CodeBuild path doesn't require it), delete the stack directly:
+
+```bash
+aws cloudformation delete-stack --stack-name <stack_name_base>
+```
+
+Like `cdk destroy`, this removes the FAST stack but not the CDK bootstrap or asset buckets.
 
 **Warning**: `cdk destroy` will delete all data including S3 buckets created during deployment and ECR images.
 

scripts/README.md

@@ -63,7 +63,7 @@ python scripts/deploy-with-codebuild.py
 
 Packages your git-tracked source and runs the full deployment in the cloud via a CodeBuild project, streaming logs to your terminal. On a **successful** build, all created resources (S3 source bucket, CodeBuild project, IAM role, permission boundary) are removed. On a **failed** build, they are retained for debugging and reused on the next run.
 
-Only git-tracked or staged files are deployed — stage or commit first, as untracked files are skipped with a warning. This does not remove your deployed FAST stack; for that, run `cd infra-cdk && cdk destroy`.
+Only git-tracked or staged files are deployed — stage or commit first, as untracked files are skipped with a warning. This does not remove your deployed FAST stack; to tear that down, run `cd infra-cdk && cdk destroy`, or `aws cloudformation delete-stack --stack-name <stack_name_base>` if you don't have CDK installed locally.
 
 The IAM role has `AdministratorAccess` constrained by a permission boundary that denies dangerous actions (`iam:CreateUser`, `iam:CreateAccessKey`, `organizations:*`, etc.) to prevent privilege escalation.