`-1 .* Eye(2)` isn't `Diagonal{T,FillVector{T}}`

[mtfishman]

For example:

julia> -1 * Eye(2)
2×2 LinearAlgebra.Diagonal{Float64, Fill{Float64, 1, Tuple{Base.OneTo{Int64}}}}:
 -1.0    ⋅ 
   ⋅   -1.0

julia> -1 .* Eye(2)
2×2 LinearAlgebra.Diagonal{Float64, Vector{Float64}}:
 -1.0    ⋅ 
   ⋅   -1.0

julia> -Eye(2)
2×2 LinearAlgebra.Diagonal{Float64, Fill{Float64, 1, Tuple{Base.OneTo{Int64}}}}:
 -1.0    ⋅ 
   ⋅   -1.0

julia> (.-)(Eye(2))
2×2 LinearAlgebra.Diagonal{Float64, Vector{Float64}}:
 -1.0    ⋅ 
   ⋅   -1.0

(dev) pkg> st FillArrays
Status `~/.julia/dev/KroneckerArrays/dev/Project.toml`
  [1a297f60] FillArrays v1.13.0

julia> versioninfo()
Julia Version 1.11.6
Commit 9615af0f269 (2025-07-09 12:58 UTC)
Build Info:
  Official https://julialang.org/ release
Platform Info:
  OS: macOS (arm64-apple-darwin24.0.0)
  CPU: 10 × Apple M1 Max
  WORD_SIZE: 64
  LLVM: libLLVM-16.0.6 (ORCJIT, apple-m1)
Threads: 1 default, 0 interactive, 1 GC (on 8 virtual cores)

Maybe related to #385 and issues linked to in that PR.

[jishnub]

Would be fixed on Julia nightly by JuliaLang/LinearAlgebra.jl#1423. We may add a specific fix in this package until that's available.