Issue: Refactor use of old vs. CMake-generated kernel dispatch lists

[OmarDuran]

It seems the kernel dispatch list may not be fully generated or at least used from the CMake templates, and there’s confusion about whether parts of the old dispatch system are still in use.

Relevant code:

GeosxMacros.cmake#L310

KernelDispatchTypeList.hpp.template#L31-L33

In PR #3765
For compositional MFD, the .cpp generation is disabled, while VEM still uses the cpp generated workflow.

Possible course of actions:

1. Confirm which dispatch mechanism is currently used (The CMake-generated dispatch should be used).
2. Decide if the old dispatch should be fully deprecated.
3. Ensure consistent handling across MFD, VEM, and other modules.