Apply consistent number-unit spacing and helper usage: - Add a space before "%" in all percentage labels (Battery, Signal Quality, TX Share, RX/TX Flood Share, RX Error Rate, Archive Free), matching the existing style of other units such as " dBm" and " dB". - Replace raw String(x) + " s" with formatDuration() for RX Air, TX Air, and Total Air in the Radio card, matching the style already used for uptime and event age.