Bump RecursiveArrayTools to v4.3.6

[ChrisRackauckas-Claude]

Please ignore until reviewed by @ChrisRackauckas.

Patch bump to release the recursivecopy fix from #636, which is currently merged to master but unregistered. That fix is the last blocker for SciML/OrdinaryDiffEq.jl#1365 — verified locally on Julia 1.11.9 with OrdinaryDiffEq v7.2.1:

• master (4.3.5 + PR Fix recursivecopy for VectorOfArray with immutable outer storage #636): the issue's MWE solves, sol.retcode == Success, outer storage preserved as VectorOfArray{Float64, 2, SVector{2, Vector{Float64}}}, max error vs the analytic solution 7.7e-12 at abstol = reltol = 1e-10
• registered v4.3.5: still fails in recursivecopy at src/utils.jl:38 with setindex!(::SVector{2, Vector{Float64}}, ...) is not defined

Bugfix only, no public API change, so a patch bump.

Depends on nothing, but #637 (downstream regression test for the same issue) is worth merging first so the release ships with coverage.

Links

• error when using VectorOfArray with underlying StaticArray OrdinaryDiffEq.jl#1365
• Fix recursivecopy for VectorOfArray with immutable outer storage #636
• Add downstream ODE regression test for immutable-outer VectorOfArray #637

🤖 Generated with Claude Code

https://claude.ai/code/session_018DPqBz4Qyy7bZzXZ3sjF45

[ChrisRackauckas-Claude]

tests / Downstream is red here on all three Julia versions, but not because of this bump — this PR changes only the version string. It is master's current state: the nested-ArrayPartition Rodas5 @test_broken in test/Downstream/odesolve.jl now reports Unexpected Pass (fixed upstream in OrdinaryDiffEqRosenbrock v2.6.1), which errors the testset.

#637 fixes it — tests / Downstream passes there on all three versions. That PR should merge before this one, so v4.3.6 is cut from a green master and ships with regression coverage for SciML/OrdinaryDiffEq.jl#1365.

The other red checks (Downgrade (Core), LabelledArrays.jl/Core, OrdinaryDiffEq.jl/Downstream, SciMLSensitivity.jl/Core1/Core4) are identical on both PRs and unrelated to this change — pre-existing breakage from upstream version drift since master last ran CI on 2026-07-24.