Investigate PTC nonlinear solver for consistent initialization

[jbreue16]

We have seen that the PCT solver works fine for the initialization tests in the CI, and at least some more SMA initialization tests that didn't work with the previous composite default.
We should continue this investigation and see if this is truly a generally more robust solution for us.

• check all SMA initialization tests, add them to CI
• test initialization settings that failed in the past

wip on test/consistent_ini

update: seems like with ptc, some tests actually failed, see e.g. https://github.com/cadet/CADET-Core/actions/runs/18743567828/job/53465439606 test of column_1D with parameter sensitivities for LWE case, which fails at the beginning of the second time section

Maybe we should still use composite, but with PTC ?

[jbreue16]

We could make consistent initialization a bachelor thesis topic, added to https://github.com/cadet/CADET-Project-Management/issues/70