Add automated test suite

[victorfrye]

Is your feature request related to a problem? Please describe. I would like increased confidence when a change occurs (from myself, dependabot, or community contributor) that core functionality is not broken or is intentionally modified.

Describe the solution you'd like Add a test suite. Probably utilizing Jest given investigations.

Describe alternatives you've considered Also considered:

• Vitest
• Playwright
• Cypress

Additional context In scope:

• [ ] add unit testing for rich models
• [ ] add component tests for rendering
• [ ] execute tests in workflow automation

out of scope:

• #123 automated UI testing