v1.6.6

Changed

• Bump MSRV to 1.73
• Bump guff_css to 0.3.2
• Bump itoa to 1.0.11
• Bump wasm-bindgen to 0.2.92
• Bump wasm-opt to 0.116.1
• Bump web-sys/js-sys to 0.3.69
• Use overflow:clip instead of overflow:hidden for sprite wrappers