- UITask::shutdown(): power GPS off using !PIN_GPS_EN_ACTIVE instead of hardcoded
LOW, matching MicroNMEALocationProvider::stop() (still LOW on current active-high
devices, but correct for a future active-low GPS).
- buzzer _noteFreq(): clamp octave to 8 instead of 7 so the parser's accepted range
(4-8) is fully consumed; previously an octave-8 digit was clamped away and could
leak into the stream as the next note's duration.
- Waypoint::readFrom(): check read() return for version/reserved/count header bytes
so a truncated file is rejected instead of using garbage count.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>