🚀 Adding new app state to handle user info

[teresaqhoang]

Motivation and Context

Added new app state for setting user info, refactored app views, and added shared styles for informative views.

This is a fix for a bug where the webapp would get stuck on the Loading Chats page. Something with SSO caused this.

Description

• The App component now transitions to a SettingUserInfo state after successfully discovering the backend, and then to the LoadingChats state after successfully setting the active user info.
• The user info status text in the App component has been updated to display a default message while fetching user information, and an error component has been added to display an error message at view level.
• A new useSharedClasses hook has been added to provide a set of shared styles for informative views.
• The BackendProbe component has also been updated to use the shared informativeView class.
• Added tesseract data files to gitignore

Contribution Checklist

• The code builds clean without any errors or warnings
• The PR follows the Contribution Guidelines and the pre-submission formatting script raises no violations
  - [ ] All unit tests pass, and I have added new tests where possible
• I didn't break anyone 😄