Upload SARIF to GitHub Code Scanning

[TheEadie]

Summary

• Extracts SARIF report path from Flyway CLI 12.2+ JSON output alongside existing HTML report
• Uploads SARIF to GitHub Code Scanning via github/codeql-action/upload-sarif@v3 in both migrations/checks and state/prepare actions
• Uses continue-on-error: true so repos without GHAS don't fail
• Only uploads when the SARIF file path is present (backward compatible with older Flyway versions)
• Adds skip-code-scanning-upload input for opt-out

Requires security-events: write permission in consuming workflows.

🤖 Generated with Claude Code