Fix negative voltage value when discharging, preventing battery time estimation

[ragotpaul]

When the computer is running on battery, the CURRENT_NOW value in the uevent file can be negative. This prevents the remaining battery time from being calculated, and only the message "Discharging" is shown.

This PR updates the logic to handle negative CURRENT_NOW values correctly so that the estimated time remaining is displayed as expected.

[Copilot]

Pull Request Overview

This PR enhances battery time estimation by properly handling negative POWER_NOW values when discharging.

• Change power check from > 0 to !== 0 so negative readings are included
• Use Math.abs for discharging time calculation
• Preserve the “Discharging” status with correct estimated time

Comments suppressed due to low confidence (1)

sensors.js:466

• Add unit tests for scenarios where POWER_NOW is negative (discharging) and positive (charging) to verify the timeLeft calculation behaves correctly in both cases.

                    timeLeft = (output['ENERGY_NOW'] / Math.abs(output['POWER_NOW']));

[corecoding]

This seems logical. Thank you. Let's give it a try!