Fix FRED play/media button transparency and disabled state #7570

Job	Run time
Mac (Debug, clang, arm64)	5m 48s
Mac (Release, clang, x86_64)	7m 20s
Windows (Debug, MSVC, x64)	15m 55s
Windows (Release, MSVC, x64)	16m 13s
Windows (Debug, MSVC, Win32)	14m 1s
Linux (Debug, gcc-13)	12m 23s
Windows (Release, MSVC, Win32)	16m 11s
Linux (Release, gcc-13, -DFSO_BUILD_WITH_OPENGL=OFF -DFSO_BUILD_WITH_VULKAN=ON)	13m 50s
Linux (Release, clang-16)	17m 13s
Linux (Debug, gcc-13, -DFSO_BUILD_WITH_OPENGL=OFF -DFSO_BUILD_WITH_VULKAN=OFF)	4m 1s
Linux (Release, gcc-13)	11m 15s
Linux (Release, gcc-9)	16m 17s
Mac (Debug, clang, x86_64)	5m 26s
Linux (Debug, gcc-13, -DFSO_BUILD_WITH_OPENGL=OFF -DFSO_BUILD_WITH_VULKAN=ON)	12m 29s
Windows (FastDebug, MSVC, Win32)	16m 13s
Windows (FastDebug, MSVC, x64)	16m 14s
Linux (Debug, gcc-9)	18m 25s
Linux (Release, gcc-13, -DFSO_BUILD_WITH_OPENGL=OFF -DFSO_BUILD_WITH_VULKAN=OFF)	7m 49s
Mac (Release, clang, arm64)	9m 34s
Linux (Debug, clang-16)	6m 52s
	4h 3m 29s

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