Upgraded wgpu to 0.17.2 to pick up a bugfix for the DirectX 12 backend where resizing the window would completely crash the program. This bug apparently did not affect the other wgpu backends
Replaced the VRC7 expansion audio implementation with a stripped-down version of the YM2413/OPLL implementation from my Sega Master System emulator, which should be more accurate and also much more efficient
Implemented the NES PPU's grayscale bit, which was only used in a single officially released game: Noah's Ark (EU) uses it for the water effect covering the bottom of the screen
Made audio buffer size configurable instead of hardcoded