Fix CI errors: remove debug display and missing hess_J field

- Remove leftover `display(S)` debug statement in coloring.jl
- Add missing `Int[]` for `hess_J` field in `_FunctionStorage` else branch

https://claude.ai/code/session_01WBu9hZukriWDSSybN9gfBq

Author: claude

src/coloring.jl

@@ -71,7 +71,6 @@ function _hessian_color_preprocess(
 
     # Perform coloring using SMC
     problem = SMC.ColoringProblem(; structure = :symmetric, partition = :column)
-    display(S)
     tree_result = SMC.coloring(S, problem, algo)
 
     # Wrap result with local_indices

src/types.jl

@@ -172,6 +172,7 @@ struct _FunctionStorage{R<:SMC.AbstractColoringResult}
                 grad_sparsity,
                 Int[],
                 Int[],
+                Int[],
                 nothing,
                 Array{Float64}(undef, 0, 0),
                 dependent_subexpressions,