`unalias`-ing

It would be nice if TransmutedDimsArray behaved like Adjoint does here:

julia> x = [1 2; 3 4]; @btime $x .= $x'  # detects aliasing, makes a copy of RHS
  23.971 ns (1 allocation: 96 bytes)
2×2 Matrix{Int64}:
 1  2
 3  4

julia> x = [1 2; 3 4]; @btime $x .= $(PermutedDimsArray(x, (2,1)))  # does not detect this
  16.784 ns (0 allocations: 0 bytes)
2×2 Matrix{Int64}:
 1  2
 2  4

julia> x = [1 2; 3 4]; @btime $x .= $(TransmutedDimsArray(x, (2,1)))  # no detection, and slow
  62.352 ns (6 allocations: 320 bytes)
2×2 Matrix{Int64}:
 1  2
 2  4

Start by reproducing the Julia examples comparing Adjoint, PermutedDimsArray, and TransmutedDimsArray during in-place assignment. Then trace TransmutedDimsArray's alias handling and compare it with the behavior of Adjoint; done means aliasing is detected and the assignment produces the correct result without the reported slowdown and allocations.