Indicate backend server status clearly and details on where the backend is located

[shrsv]

git-lrc works both with self-hosted LiveReview backends, or cloud livereview.hexmos.com

Authentication depends on backend, for example. And sometimes we are under illusion that cloud is the backend, but the config actually connects to some local non-existant url.

Potential solution:

1. Have a health API to the server
2. have an indicator in "lrc ui" make it green/yellow based on connection status
3. On hover - show more details on backend being used

Implementation Details:

• Perform health check once when starting lrc ui
• Re-check on page refresh
• Display persistent status indicator in the UI
• Avoid excessive polling - only check when user-initiated