fluidsimfoam-restart command

We have the commands fluidsim-restart and snek-restart, implemented with https://foss.heptapod.net/fluiddyn/fluidsim/-/blob/branch/default/lib/fluidsim_core/scripts/restart.py

in

• https://foss.heptapod.net/fluiddyn/fluidsim/-/blob/branch/default/fluidsim/util/scripts/restart.py
• https://github.com/snek5000/snek5000/blob/main/src/snek5000/util/restart.py

We need to have the same type of command for fluidsimfoam...

• Requires #37 (closed)
• Useful in particular for #32