Unit tests (PlatformIO Unit Testing / Unity) go here.

Planned first test: EL512Panel::encodeRow() - check that HS is high for exactly
256 clocks per visible row, VS appears only on the last blanking line, that x = 0
(datasheet column 1, odd) lands on TVID and x = 1 on VID, and that clock c is
stored at index c ^ 2 (8-bit I2S byte order).

Run with:  pio test -e esp32dev

More info: https://docs.platformio.org/en/latest/advanced/unit-testing/index.html