Feature/optimize headers #3679

Job	Run time
Build sdist and set version	46s
build-cpp-test-linux (debug, gcc)	18m 14s
build-cpp-test-linux (debug, clang)	10m 53s
build-cpp-test-linux (release, gcc)	39m 45s
build-cpp-test-linux (release, clang)	18m 14s
build-cpp-test-macos (debug)	11m 35s
build-cpp-test-macos (release)	17m 45s
build-cpp-test-windows (debug, msvc)	12m 38s
build-cpp-test-windows (debug, clang-cl)	16m 32s
build-cpp-test-windows (release, msvc)	19m 17s
build-cpp-test-windows (release, clang-cl)	20m 31s
Build and test in Conda (ubuntu)	3m 51s
Build and test in Conda (windows)	6m 4s
build-and-test-python (linux-x64)	10m 30s
build-and-test-python (linux-aarch64)	32m 15s
build-and-test-python (macos)	9m 58s
build-and-test-python (windows)	14m 8s
test-python-macos-arm64	0s
publish-wheels	21s
	4h 23m 17s

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