Universal Inbox UI

A visual and usability release focused on making RelayDesk feel like one serious client for email, messages and work communication rather than an empty feed demo.

What changed

• Rebuilt /rd1-app/ around a Slack-style application shell.
• Added populated sample conversations for Outlook, Gmail, WhatsApp, Teams, Slack, Telegram, SMS and Matrix.
• Added Universal Inbox, Priority, Email, Messages and Work navigation.
• Added richer source/account labels, unread counts and conversation metadata.
• Retained desktop conversation pane and mobile app-style conversation view.
• Retained Matrix connect, sync and text-send developer-preview flow.
• Widened and simplified the white product preview on /rd1/ so it no longer looks like a narrow phone window.
• Kept Matrix as a pluggable communication backend while RelayDesk owns the canonical feed and application-core state.

The multi-provider inbox shown in Sample workspace is demonstration data. Live private accounts require a real reviewed bridge or direct provider adapter. Web remains the primary product direction; the older Windows line is retained only as secondary/archive material.