- CPU sleep: board.sleep(0) in main loop puts NRF52 into WFE/sd_app_evt_wait
between iterations; wakes on any interrupt (radio, BLE, timer). Largest
power saving of the three changes.
- VBAT_ENABLE gating: voltage divider now powered only during ADC read
(HIGH for 10ms, then LOW). Previously stayed HIGH continuously.
Fixed in both variant.cpp (init) and WioTrackerL1Board::getBattMilliVolts().
- LED off with display: PIN_LED is cleared when auto-off triggers and
restored (handed back to userLedHandler) when display wakes. Avoids
idle LED current draw during screen-off periods.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
