[Test] Add integration test

[yuhueilee]

Description

Implement integration tests for the application using mock service worker.

References

• ReferenceError: TextEncoder is not defined (updating to v2) mswjs/msw#1796
• HttpResponse.json() throwing TypeError: Right-hand side of 'instanceof' is not an object. mswjs/msw#2076
• MSW: debug runbook for intercepting requests and mocking responses
• MSW: avoid request assertions
• Differences between userEvent and fireEvent

  • The problem is that the browser usually does more than just trigger one event for one interaction. For example, when a user types into a text box, the element has to be focused, and then keyboard and input events are fired and the selection and value on the element are manipulated as they type.

• https://playwright.dev/docs/test-webserver