Rename io.h/cpp to iobase to avoid conflicts. Closes #3662 #1491

Job	Run time
Copy the font files	6s
Build ubuntu-20.04-g++-10	4m 50s
Build ubuntu-20.04-g++-11	4m 51s
Build ubuntu-22.04-g++-12	5m 29s
Set up and cache emscripten	1m 50s
Build ubuntu-20.04-clang-10	5m 13s
Build ubuntu-20.04-clang-11	5m 29s
Build ubuntu-20.04-clang-12	5m 8s
Build macos-latest-xcode-13.1	7s
Build macos-latest-xcode-14.2	8s
Build macos-11-g++-12	10m 27s
Build JS toolkit (nohumdrum, Building toolkit without humdrum, -c -H -M, verovio-toolkit.js*)	4m 43s
Build JS toolkit (light, Building toolkit without humdrum as light version, -c -H -l -M, verovio-...	4m 53s
Build JS toolkit (wasm, Building toolkit without humdrum as wasm, -c -H -w -M, veroviowasm, true)	5m 27s
Build JS toolkit (default, Building default toolkit with humdrum, -c -M, -hum.js)	7m 44s
Check settings for deployment	0s
Build documentation	0s
Deploy JS toolkit	0s
Deploy documentation	0s
Skip deployment if set	0s
	1h 6m 25s

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