[RomApp] Use NumpyOutputProcess in RomManager rather than RomBasisOutputProcess

[Rbravo555]

📝 Description

For a while, the RomManager contained the following comment:

# FIXME:
# - Use a method (upcoming) for smoothly retrieving solutions. In here we are using the RomBasisOutput process in order to store the solutions

This PR introduces direct snapshot handling inside RomManager, eliminating the reliance on RomBasisOutputProcess and avoiding holding snapshots of a single simulation in RAM unnecessarily.

Note: Future PRs will address the SVD computation for full scalability and usability. In this PR, although snapshots are flushed every step (or at a user-defined interval), they are still loaded back into RAM to compute the SVD. A future PR will introduce an alternative using partitioned methods or libraries like dask or dislib.

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🆕 Changelog

• Refactor: Stopped using RomBasisOutputProcess to store snapshots in RomManager.
• Feature: Implemented SVD logic directly within RomManager (mirroring RomBasisOutputProcess).
• Fix: Modified SetUpSimulationInstance to give precedence to parameters passed by RomManager.

[NicolasSR]

The changes look good to me. Are we using RomBasisOutputProcess anywhere else still? Otherwise, why not remove it completely here?

[Rbravo555]

The changes look good to me. Are we using RomBasisOutputProcess anywhere else still? Otherwise, why not remove it completely here?

I've erased the references to the RomBasisOutputProcess, but kept the file itself, because it is used in a test in the Co-Simulation application. In order to avoid adding Co-simulation into this PR, I added a deprecation warning to the class. In a future PR we can erase the class and modify the Co-Simulation test that uses it.

[Marco1410]

Approved.