ci: Add Automated Code Formatting and Style Checks

[carlagesa]

To ensure our Terraform code is readable and consistent, we should automate code formatting. The terraform fmt command should be run as part of our CI pipeline. This will automatically format all .tf files according to the canonical HCL style, reducing cognitive load during code reviews and maintaining a clean codebase.

Acceptance Criteria:

• A new step is added to the CI/CD pipeline that runs terraform fmt -check.
• The pipeline will fail if any files are not correctly formatted.
• The README is updated to encourage developers to run terraform fmt locally before committing.