[CI Broken] Multiple test failures due to JET incompatibility with Julia 1.13 and dependency resolution issues

[ChrisRackauckas-Claude]

Summary

CI health check detected multiple test failures across different Julia versions and platforms. The failures are due to:

1. JET compatibility issue with Julia 1.13-alpha (pre-release) - JET.jl appears incompatible with Julia 1.13.0-alpha2
2. Dependency resolution failures affecting both Julia 1.13-alpha and Julia 1.10 (Core tests)
3. Test errors on Julia 1.12 (stable versions) - JET linting error causing test suite to fail

Failed CI Jobs

Julia 1.13-alpha (pre-release) - All platforms

• macOS, Ubuntu, Windows - All failing with dependency resolution errors
• Error: Unsatisfiable requirements detected for package JET
• Root cause: JET package (restricted to versions 0.8-0.11) has no versions compatible with Julia 1.13.0-alpha2
• Logs: https://github.com/SciML/ModelingToolkitNeuralNets.jl/actions/runs/20789621224

Julia 1.10 (Core)

• Platform: All
• Error: Unsatisfiable requirements detected for package DifferentiationInterface
• Root cause: DifferentiationInterface (restricted to 0.6-0.7) incompatible with Julia 1.10 in the Core test configuration
• Logs: https://github.com/SciML/ModelingToolkitNeuralNets.jl/actions/runs/20789621166

Julia 1.12 (stable) - All platforms

• macOS, Ubuntu, Windows - Test errors due to JET incompatibility
• Error: JET test throwing exception: Expected MethodTableView error in invoke_mt_compiler
• Test result: 29 passed, 0 failed, 1 errored, 1 broken
• Logs: https://github.com/SciML/ModelingToolkitNeuralNets.jl/actions/runs/20789621224/job/59708356898

Error Details

JET Error (Julia 1.12+)

Code linting (JET.jl): Error During Test
Expression: (JET.report_package)(ModelingToolkitNeuralNets; toplevel_logger = nothing, target_defined_modules = true)
Expected MethodTableView
Stacktrace:
  [1] error(s::String)
    @ Base ./error.jl:44
  [2] invoke_mt_compiler(::Core.MethodTable, ::Symbol, ::Type, ::Vararg{Any})
    @ Base ./reflection.jl:279

Dependency Resolution Error (Julia 1.13-alpha)

ERROR: LoadError: Unsatisfiable requirements detected for package JET [c3a54625]:
 JET [c3a54625] log:
 ├─possible versions are: 0.0.1 - 0.11.3 or uninstalled
 ├─restricted to versions 0.8 - 0.11 by project [4a281450], leaving only versions: 0.8.0 - 0.11.3
 │ └─project [4a281450] log:
 │   ├─possible versions are: 0.0.0 or uninstalled
 │   └─project [4a281450] is fixed to version 0.0.0
 └─restricted by julia compatibility requirements to versions: uninstalled — no versions left

Suggested Fix Approaches

1. Short-term: Consider making JET tests optional or skipping them for Julia 1.12+ until JET is updated
2. Medium-term: Update JET version bounds in Project.toml when a compatible version is released
3. Long-term: Monitor JET.jl repository for Julia 1.12/1.13 compatibility updates
4. Core tests: Investigate DifferentiationInterface compatibility constraints for Julia 1.10

Additional Notes

• LTS version (Julia 1.6): ✅ All tests passing
• Documentation build: ✅ Passing
• Spell check: ✅ Passing
• Runic formatting: ✅ Passing

The core functionality appears sound - only QA tooling (JET) and pre-release Julia versions are affected.

CI Health Check PR

This issue was discovered during an automated CI health check: #100

cc: @ChrisRackauckas