Add basic precompilation workload

[rikhuijzer]

This PR suggests adding a basic precompile workload now that caching works for inferred (since 1.8) and binary (since 1.9) code.

For people unfamiliar with SnoopPrecompile, the idea is to compile code during the precompilation phase which can then be used during later phases. More specifically, precompilation runs only when installing the package while later phases run every time that you restart Julia. In other words, the benefit of adding workloads to the precompilation phase is that more code will be compiled at an earlier point, which will then reduce the Time To First X (TTFX).

Below, the benchmark shows that this PR will increase the precompilation time by 13 - 2 = 11 seconds while it will reduce the TTFX for a basic workload by 10 - 2 = 8 seconds. Over time, it is expected that these benefits will add up if more and more package maintainers precompile larger parts of their codebase.

Benchmark

With Julia 1.9.0-rc2.

Before this PR

$ julia --project

(MLJ) pkg> precompile
Precompiling environment...
  1 dependency successfully precompiled in 2 seconds. 91 already precompiled.

julia> @time using MLJ
  1.725931 seconds (2.83 M allocations: 188.124 MiB, 3.06% gc time, 50.73% compilation time: 88% of which was recompilation)

julia> @time include("src/precompile.jl")
 10.005304 seconds (25.71 M allocations: 1.648 GiB, 4.45% gc time, 99.05% compilation time: <1% of which was recompilation)

After this PR

$ julia --project

(MLJ) pkg> precompile
Precompiling environment...
  1 dependency successfully precompiled in 13 seconds. 91 already precompiled.

julia> @time using MLJ
  2.004735 seconds (3.48 M allocations: 226.616 MiB, 3.51% gc time, 45.24% compilation time: 89% of which was recompilation)

julia> @time include("src/precompile.jl")
  3.062700 seconds (6.84 M allocations: 448.673 MiB, 3.79% gc time, 97.12% compilation time)

[codecov-commenter]

Codecov Report

Merging #1016 (2144ad7) into dev (ec999a1) will decrease coverage by 11.28%. The diff coverage is 0.00%.

@@             Coverage Diff             @@
##              dev    #1016       +/-   ##
===========================================
- Coverage   42.85%   31.57%   -11.28%     
===========================================
  Files           1        2        +1     
  Lines          28       38       +10     
===========================================
  Hits           12       12               
- Misses         16       26       +10     

Impacted Files	Coverage Δ
src/precompile.jl	0.00% <0.00%> (ø)

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[rikhuijzer]

Let's wait with this PR until https://github.com/JuliaLang/Precompiler.jl is published. They are currently discussing naming in issue 2.

[ablaom]

Closing in favour of adding workloads added to component packages. See also https://github.com/JuliaAI/MLJBase.jl/issues/924