refactor: move StdLibs into extensions
Created by: avik-pal
julia> @time_imports using KernelAbstractions
10.1 ms UnsafeAtomics
6.6 ms Atomix
0.7 ms StaticArraysCore
169.4 ms StaticArrays
0.4 ms Adapt
0.2 ms AdaptStaticArraysExt
1.9 ms CEnum
0.2 ms LazyArtifacts
┌ 1.5 ms LLVMExtra_jll.__init__()
100.0 ms LLVMExtra_jll 97.66% compilation time
┌ 0.2 ms LLVM.__init__()
30.7 ms LLVM
2.8 ms UnsafeAtomicsLLVM
12.1 ms KernelAbstractions
0.2 ms StaticArrays → StaticArraysStatisticsExt
Moves both LinearAlgebra and SparseArrays into extensions. Saves around 250ms in load times (see #506)