Move tutorials with G3D classes into `legacy/g3d` #15923

Job	Run time
mac13 ARM64 LLVM_ENABLE_ASSERTIONS=On, builtin_zlib=ON	24m 45s
mac14 X64 LLVM_ENABLE_ASSERTIONS=On, CMAKE_CXX_STANDARD=20	1h 51m 55s
fedora40 LLVM_ENABLE_ASSERTIONS=On, CMAKE_CXX_STANDARD=20	34m 8s
Windows 10 x64 Release	2h 16m 6s
mac15 ARM64 LLVM_ENABLE_ASSERTIONS=On, CMAKE_CXX_STANDARD=20	26m 32s
fedora41 LLVM_ENABLE_ASSERTIONS=On	37m 35s
Windows 10 x86 Release	1h 1m 35s
mac-beta ARM64 LLVM_ENABLE_ASSERTIONS=On, CMAKE_CXX_STANDARD=20	36m 49s
alma8 LLVM_ENABLE_ASSERTIONS=On	30m 30s
Upload Event Payload	2s
alma9 LLVM_ENABLE_ASSERTIONS=On, CMAKE_BUILD_TYPE=Debug	59m 11s
ubuntu22 imt=Off, LLVM_ENABLE_ASSERTIONS=On, CMAKE_BUILD_TYPE=Debug	1h 33m 7s
ubuntu2404 LLVM_ENABLE_ASSERTIONS=On, CMAKE_BUILD_TYPE=Debug	1h 52m 19s
ubuntu2410 LLVM_ENABLE_ASSERTIONS=On, CMAKE_BUILD_TYPE=Debug	1h 12m 29s
debian125 LLVM_ENABLE_ASSERTIONS=On, CMAKE_CXX_STANDARD=20	27m 30s
alma9 modules_off runtime_cxxmodules=Off	34m 48s
alma9 march_native CMAKE_BUILD_TYPE=RelWithDebInfo, CMAKE_CXX_FLAGS=-march=native, CMAKE_C_FLAGS=-march=native, fortran=OFF	28m 10s
alma9 arm64 CMAKE_BUILD_TYPE=RelWithDebInfo	34m 18s
alma9-clang clang LLVM_ENABLE_ASSERTIONS=On, CMAKE_C_COMPILER=clang, CMAKE_CXX_COMPILER=clang++	24m 13s
	16h 26m 2s

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