BlueAI design previews

Design previews attached to Jira tickets.

• ROB-21300: application confirmation screen with the inbox hint (desktop, mobile)
• ROB-21309 sign-in page (replaces the now.gg login): BlueAI (bluestacks.ai and app), onBlue (onblue.ai)
• BlueAI install page (sheet #6): Mac, Windows
• ROB-21300 emails: waitlist and acceptance emails as they should render