Fix bug in thruster zeroing and improve negative thrust reallocation in forceTorqueThrForceMapping

[E-Krantz]

Describe your use case
There is a bug in the forceTorqueThrForceMapping module where the check for zero rows in the DG matrix uses a hardcoded value instead of the actual number of thrusters. This causes incorrect zeroing of thrusters in some cases.

Additionally, the current thrust allocation logic can assign positive force to thrusters that are orthogonal to the desired force direction, due to adding the minimum force across all thrusters. This can result in non-physical outputs.

I have a solution to both of these issues, which implements an improved algorithm for handling negative thruster forces and will create a PR.

Describe alternative solutions you've considered
N/A

Additional context
This issue tracks both fixing the zeroing bug and implementing an improved, iterative reallocation algorithm that disables thrusters producing negative forces, reallocating force only to valid thrusters, yielding more physical and correct allocations.

[schaubh]

Thanks, I'll take a look at the PR.