v3.0.0

Breaking changes

• Switched from CommonJS to ES modules — consumers using require() must switch to import or dynamic import()
• Circular references now throw Error('Circular reference detected') instead of causing a stack overflow

Improvements

• Modernized tooling: ESLint flat config, node:test, c8 coverage
• Replaced Travis CI with GitHub Actions (Node 18, 20, 22, 24)
• Added engines field requiring Node >= 18
• Added exports field for proper ESM resolution
• Added files field for leaner published package