Allow LinearSolve 5

[ChrisRackauckas-Claude]

Please ignore this draft until it has been reviewed by @ChrisRackauckas.

Summary

• Allow LinearSolve 5 in addition to the existing LinearSolve 4 compatibility range.
• Bump ExponentialUtilities from 1.33.1 to 1.33.2.

Why

NonlinearSolve 4.23 requires LinearSolve 5.0.1. OrdinaryDiffEq's nonlinear-solver stack also includes OrdinaryDiffEqLinear, whose ExponentialUtilities dependency still restricted the environment to LinearSolve 4. That made the combined environment unsatisfiable even though ExponentialUtilities' existing cached LinearSolve paths work with v5.

This is a compatibility-only prerequisite; no ExponentialUtilities implementation changes are needed.

Validation

Run locally on Julia 1.12.6 with LinearSolve 5.0.1:

• GROUP=Core julia +1.12 --project=. -e 'using Pkg; Pkg.test()': exit 0, 679 passed and 1 pre-existing broken test.
• GROUP=QA julia +1.12 --project=. -e 'using Pkg; Pkg.test()': exit 0, 20 passed and 1 pre-existing broken test.
• Repository-wide Runic check: exit 0.
• git diff --check: exit 0.

[ChrisRackauckas-Claude]

CI checkpoint (2026-07-22 07:21 EDT): ExponentialUtilities Core on all Julia/OS lanes, QA, GPU, docs, downgrade, Runic, and OrdinaryDiffEq InterfaceI/II/IV/V all passed. The only failures were OrdinaryDiffEq InterfaceIII on macOS, Linux, and Windows. The original test reproduces on untouched OrdinaryDiffEq master with LinearSolve 4.3.0; the independent root cause and public-API test fix are documented in SciML/OrdinaryDiffEq.jl#3983. No ExponentialUtilities implementation change is indicated by those failures.