[UI] Main page

[Nefariusek]

As a user, I want to see the main menu when I enter the app.

Acceptance criteria

Verify, consult and update before starting.

• Main menu shows random quotes about animals.
• There are 4 buttons labelled:
  ** Start quiz - navigates to the quiz settings page.
  ** Leaderboard - navigates to leaderboard page.
  ** Adoption - navigates to the adoption page.
  ** Credits - navigates to the credits page.

Additional notes

• Follow the UI project from miro.
• Use placeholder quote and default buttons - it will be implemented in the following stories.
• For now, use alert() as a temporary solution for navigation.
• This functionality should be stored in a separate .js file.