Following C++ Core Guidelines, Oct 3, 2024:

 - "By default, make member functions `const`", https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#Rconst-fct
 - "Don’t make a function `virtual` without reason", https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#Rh-virtual

Following C++ Core Guidelines, Oct 3, 2024, "Avoid `protected` data", https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#c133-avoid-protected-data

Following C++ Core Guidelines, Oct 3, 2024, "For “out” output values, prefer return values to output parameters", https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#Rf-out

Following C++ Core Guidelines, Oct 3, 2024, "For “out” output values, prefer return values to output parameters", https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#Rf-out

Each of those duplicated typedefs were only used once, to declare a local `computeJacobianTerms` variable.

Also added `const` to those local variables.