Adds an Amazon Bedrock Guardrail (PROMPT_ATTACK, HIGH, input) plus a dedicated
least-privilege IAM user for Fusion's AWS-Guardrail integration, so the gateway
screens inbound prompts for injection/jailbreak before de-id or the agent run.
Outputs the region/id/version/access-key for the Fusion console (secret stays in
gitignored state). Verified live: benign -> NONE, injection -> GUARDRAIL_INTERVENED.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
