Add generic CP model builder and test its use in ARX model

[davidGG271]

Summary

This PR introduces a generic builder for CP models that allows constructing a MiniZinc model directly from a list of components and their associated CP constraint generators.

Changes

• Added build_generic_cp_model_from_dictionary to MznModel, enabling generic construction of CP models from component–model mappings.
• Added a unit test that validates the new builder using MznXorDifferentialModelARXOptimized.
• The test applies fixed input/output constraints and solves the resulting CP model to ensure correctness.

Notes

• The generic builder is model-agnostic and does not assume ARX-specific initialization.
• ARX-specific constraints (init_constraints) are applied explicitly in the test where required.
• This keeps the builder reusable for future CP models beyond ARX.

This change improves modularity and reusability of CP model construction, making it easier to extend support for additional CP-based models without duplicating build logic.