Add CI/CD workflows for Go library

[JAORMX]

Summary

• Add GitHub Actions workflows for linting, testing, and security scanning
• Configure golangci-lint adapted from toolhive with Go library-appropriate linters
• Add Taskfile for local development tasks
• Set up Renovate for automated dependency updates
• Add SPDX license header enforcement

Workflows

Workflow	Purpose
ci.yml	Main orchestrator - triggers on PRs and pushes to main
lint.yml	golangci-lint with build cache
test.yml	Unit tests with race detection (Codecov commented out pending provisioning)
security.yml	govulncheck + Trivy vulnerability scanning
license-headers.yml	SPDX header verification

Local Development

task lint        # Run linters
task test        # Run tests with race detection
task test-coverage  # Run tests with coverage report
task license-fix # Add missing license headers

Test plan

• Verify CI workflows run successfully on this PR
• Test task lint locally
• Test task test locally

🤖 Generated with Claude Code