Support manifold geometries in FEniCS

[jorgensd]

Missing functionality pointed out by @andre-massing.
Add support for arbitrary order curved manifolds with DOLFINx.

[jorgensd]

Example from Andre:

from mpi4py import MPI
from petsc4py import PETSc
from slepc4py import SLEPc
from packaging.version import Version
import dolfinx.fem.petsc
import numpy as np
import ufl
import pyvista
import ngsPETSc.utils.fenicsx as ngfx

from netgen.occ import *
from netgen.meshing import MeshingStep
from math import sin, cos, pi
from netgen.webgui import Draw

def Curve(t): return Pnt(0, 3+1.5*cos(t), sin(t))
n = 100
pnts = [Curve(2*pi*t/n) for t in range(n+1)]

spline = SplineApproximation(pnts)
f = Face(Wire(spline))

torus = f.Revolve(Axis((0,0,0), Z), 360)
torus_geo = OCCGeometry(torus)
Draw(torus)

ngmesh = torus_geo.GenerateMesh(maxh=0.5, perfstepsend=MeshingStep.MESHSURFACE)
Draw(ngmesh)
meshing_options = {"perfstepsend" : MeshingStep.MESHSURFACE}

geoModel = ngfx.GeometricModel(torus_geo, MPI.COMM_WORLD)
mesh, (ct, ft), region_map = geoModel.model_to_mesh(gdim=3, hmax=0.5, meshing_options=meshing_options)


order = 8
mesh = geoModel.curveField(order)

# mesh, (ct, ft), region_map = geoModel.model_to_mesh(gdim=3, hmax=0.3, meshing_options={})

with dolfinx.io.VTXWriter(mesh.comm, "mesh.bp", mesh) as bp:
    bp.write(0.0)

# with dolfinx.io.XDMFFile(mesh.comm, "manifold.xdmf", "w") as xdmf:
#     xdmf.write_mesh(mesh)
#     xdmf.write_meshtags(ct, mesh.geometry)
#     mesh.topology.create_connectivity(mesh.topology.dim-1, mesh.topology.dim)
#     xdmf.write_meshtags(ft, mesh.geometry)

grid = pyvista.UnstructuredGrid(*dolfinx.plot.vtk_mesh(mesh))
grid.cell_data["ct"] = ct.values

plotter = pyvista.Plotter()
plotter.add_mesh(
    grid, show_edges=True, scalars="ct", cmap="blues", show_scalar_bar=False
)
plotter.view_xy()
if not pyvista.OFF_SCREEN:
    plotter.show()

[jorgensd]

@UZerbinati can we merge this?:)

[jorgensd]

and then make a new release so that I can use this through pypi?:)

[UZerbinati]

Happy to merge, but for the release it would be ideal to wait for a couple until mid March, because we are waiting to release some fix also for Firedrake side of things :)