v3: CutFEm for FSI
todo:
- smoother extension of w
- unstable solution for large viscosity difference (10^4) -> look at cut_weights
- dual problem for prescribed solid
- alternative formulation: (grad(p),v) instead of (p, div(v))
- linear solver convergence for Q2/Q1
- alternative ghost penalization -> Direct Penalty
- Level Set functionality
- FSI with Translation - Deformation split
- no convergence for RT elements