Terraform AWS High-Availability Infrastructure

I need a clean, reusable Terraform stack that spins up a highly-available AWS foundation for three separate environments—development, staging, and production—using an Application Load Balancer out front. The code should provision EC2 instances behind the ALB, S3 buckets for each stage, and all the supporting IAM roles and policies.

I already rely on GitHub Actions for CI/CD, so the repository you deliver must include a simple workflow that runs terraform fmt, init, validate, plan, and apply on push to the appropriate branch. No manual tweaks after a merge; the pipeline should take it from there.

Deliverables I will review:

• main.tf (or modular equivalents) and variables.tf ready for `terraform init`
• a diagram that makes it obvious how your provisioning sequence achieves high availability across the three environments
• a screenshot (or set of screenshots) from the AWS console confirming the ALB, EC2 instances, and S3 buckets are live in each environment

Acceptance will be based on a successful `terraform apply`, the ALB reporting healthy targets, and the workflow completing without human intervention.