Issue: Align test scripts with project structure and implement CI #2
Description
The current test suite is disconnected from the actual file tree. test:unit references a non-existent state-manager.test.js, and dom-helpers.test.js is not currently integrated into the test runner. Additionally, the repository lacks automated validation.
Tasks:
Fix Test Paths: Update package.json scripts to point to existing test files.
True Unit Testing: Refactor tests to import and exercise actual production modules instead of testing duplicate function definitions within the test files.
GitHub Actions: Create .github/workflows/ci.yml to run lint, unit tests, type-check, and playwright (chromium) on every PR and push to main.