Add testing suite for web extension

[Jyyjy]

There are no current tests for the browser extension. Browser extension tests can be added to the existing cypress tests.

https://docs.cypress.io/api/plugins/browser-launch-api#Add-browser-extensions

[EandrewJones]

Updating with additional requirements:

• [x] regression tests by feature (some features already covered in core test suite)
• [x] integration tests per browser (currently covering Edge, Chrome, Firefox)

[EandrewJones]

Update (06/4/2024): Trying to organize Cypress files to get them to work with typescript.

[EandrewJones]

Closed by #466