[ENHANCEMENT] Add polar decomposition and orthogonalization #47
Description
Add polar decomposition and orthogonalization based one the corresponding functions in MatrixAlgebraKit.jl: https://quantumkithub.github.io/MatrixAlgebraKit.jl/stable/user_interface/decompositions/#Polar-Decomposition, https://quantumkithub.github.io/MatrixAlgebraKit.jl/stable/user_interface/decompositions/#Orthogonal-Subspaces. Followup to #36.