Adjust remaining supply as needed.

1. Update the remaining supply when TARE loads (from being turned on or
   the device booting up) in case the battery level changed
   significantly since the last time it was on.
2. Don't let the remaining supply go negative since that would
   negatively impact allowing free actions.

Bug: 242605499
Bug: 242769323
Test: atest --rerun-until-failure 100 CtsAlarmManagerTestCases:BasicApiTests
Change-Id: I2659c5823baab45dc3f40cbbe85078a03c5ce5fe