add Trivy IaC security scanning workflow

[EmmanuelNwa247]

Summary

Adds a Trivy IaC security scanning workflow to NEDSS-Infrastructure (DEV-328). This scans Terraform files for misconfigurations, embedded secrets, and dependency vulnerabilities on PRs and pushes to main, with results uploaded to the GitHub Security tab via SARIF.

Details

Scan scope: terraform/aws/modules/ and terraform/azure/modules/ — scoped to our reusable modules to keep findings actionable and avoid noise from external third-party module references
Scanners: vuln, secret, misconfig
Severity: CRITICAL, HIGH
Exit code set to 0 (report-only) for initial rollout — can be changed to 1 to enforce as a PR gate
Trivy action pinned to SHA per org convention (supply chain mitigation)

[github-advanced-security]

You are seeing this message because GitHub Code Scanning has recently been set up for this repository, or this pull request contains the workflow file for the Code Scanning tool.

What Enabling Code Scanning Means:

• The 'Security' tab will display more code scanning analysis results (e.g., for the default branch).
• Depending on your configuration and choice of analysis tool, future pull requests will be annotated with code scanning analysis results.
• You will be able to see the analysis results for the pull request's branch on this overview once the scans have completed and the checks have passed.

For more information about GitHub Code Scanning, check out the documentation.

[szamfir-skylight]

Looks good, thanks!

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud