[BREAKING] Move sparse functionality into package extensions

[gdalle]

Warning

Breaking changes:

• DenseSparsityDetector requires loading SparseArrays.jl
• Sparse Jacobians and Hessians require loading SparseMatrixColorings.jl
• GreedyColoringAlgorithm no longer re-exported from SparseMatrixColorings.jl

DI source

• Remove dependency on SparseArrays and SparseMatrixColorings
• Remove sparse AD functionalities

DI extensions

• Add DISparseArraysExt for DenseSparsityDetector
• Add DISparseMatrixColoringsExt for sparse Jacobians and Hessians

DI docs

• Document the move to extensions

---

Load time before:

julia> @time_imports using DifferentiationInterface
      2.5 ms  ADTypes
      0.6 ms  Compat
      0.2 ms  Compat → CompatLinearAlgebraExt
               ┌ 0.0 ms DocStringExtensions.__init__() 
     38.3 ms  DocStringExtensions 96.38% compilation time
     51.8 ms  FillArrays
      0.2 ms  PackageExtensionCompat
               ┌ 0.8 ms SuiteSparse_jll.__init__() 
      1.1 ms  SuiteSparse_jll
               ┌ 5.9 ms SparseArrays.CHOLMOD.__init__() 95.92% compilation time
    151.7 ms  SparseArrays 3.76% compilation time
      2.3 ms  FillArrays → FillArraysSparseArraysExt
     25.3 ms  DataStructures
      1.3 ms  SparseMatrixColorings
               ┌ 0.0 ms DifferentiationInterface.__init__() 
      4.4 ms  DifferentiationInterface

Load time after:

julia> @time_imports using DifferentiationInterface
      2.9 ms  ADTypes
      0.5 ms  Compat
      0.2 ms  Compat → CompatLinearAlgebraExt
               ┌ 0.0 ms DocStringExtensions.__init__() 
     32.2 ms  DocStringExtensions 96.94% compilation time
     46.6 ms  FillArrays
      0.2 ms  PackageExtensionCompat
               ┌ 0.0 ms DifferentiationInterface.__init__() 
      3.1 ms  DifferentiationInterface

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.53%. Comparing base (de23245) to head (2c97d9d).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #448   +/-   ##
=======================================
  Coverage   98.53%   98.53%           
=======================================
  Files         105      107    +2     
  Lines        4293     4295    +2     
=======================================
+ Hits         4230     4232    +2     
  Misses         63       63           

Flag	Coverage Δ
DI	98.68% <100.00%> (+<0.01%)	⬆️
DIT	98.22% <ø> (ø)

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