9aa305700c
Replace simple threshold-based grayscale quantization with ordered dithering using a 4x4 Bayer matrix. This eliminates color banding artifacts and produces smoother gradients on e-ink display. - Add 4x4 Bayer dithering matrix for 16-level threshold patterns - Modify grayscaleTo2Bit() to use pixel position for dithering - Simulates smooth grayscale transitions in BW mode without flicker