panel: denser Status layout with true two-column cards

Pair Machine|Processes, queue|cert, and sockets|hostname; fix .split
auto-margins so cards fill half the row; trim Status prose and machine
details; drop the page section index; note panel-docs on the roadmap.

Co-authored-by: Cursor <cursoragent@cursor.com>

internal/health/socket.go

@@ -36,7 +36,7 @@ func CheckSocket(name, path string, required bool) Socket {
 	default:
 		s.Present = true
 		s.Status = StatusOK
-		s.Detail = "Listening."
+		s.Detail = "Listening"
 	}
 	return s
 }