Feat/polynomial model

[hflesche]

• New models are added for pressure sensitivity, as well as an abstract base class and tests.
• Optimisation utilities are moved to a separate module to avoid circular imports.

[Copilot]

Pull Request Overview

Adds a new family of pressure sensitivity models (polynomial plus friable and patchy cement dry bulk/shear models) with a shared abstract BasePressureModel, refactors existing exponential and sigmoidal models to use the common interface, and relocates optimisation utilities to a dedicated optimisation_utilities package to avoid circular imports. Also introduces extensive new test suites (unit, integration, performance/benchmark) and updates imports accordingly. Key API change in patchy_cement_model introduces a new patchy_cement_model_dry function while altering the return signature of patchy_cement_model_cem_frac.

• Introduces BasePressureModel and new Polynomial, Friable, and PatchyCement pressure models
• Relocates optimisation helpers to rock_physics_open.equinor_utilities.optimisation_utilities
• Alters patchy_cement_model_cem_frac return values (potential breaking change) and adds large new test coverage including benchmarks

Reviewed Changes

Copilot reviewed 28 out of 30 changed files in this pull request and generated 22 comments.

Show a summary per file

File	Description
tests/t_matrix_model_tests/test_t_matrix_optimisation.py	Updated import path to new optimisation utilities module.
tests/t_matrix_model_tests/test_opt_param_to_ascii.py	Updated import for opt_param_to_ascii to new module location.
tests/machine_learning_utilities_test/test_pressure_models_benchmark.py	Added performance and memory benchmark tests for new/updated pressure models.
tests/machine_learning_utilities_test/test_pressure_models.py	Comprehensive unit/integration tests for all pressure model classes.
tests/machine_learning_utilities_test/conftest.py	Added fixtures, parametrization, and markers for pressure model testing.
src/rock_physics_open/t_matrix_models/*	Refactored imports to new optimisation utilities location.
src/rock_physics_open/t_matrix_models/init.py	Removed re-export of optimisation utilities (now relocated).
src/rock_physics_open/t_matrix_models/carbonate_pressure_substitution.py	Adjusted run_regression import path.
src/rock_physics_open/sandstone_models/*	Updated optimisation utility imports; added patchy_cement_model_dry export.
src/rock_physics_open/sandstone_models/patchy_cement_model.py	Added patchy_cement_model_dry and changed patchy_cement_model_cem_frac return signature.
src/rock_physics_open/equinor_utilities/optimisation_utilities/init.py	New package initializer exporting optimisation routines.
src/rock_physics_open/equinor_utilities/machine_learning_utilities/base_pressure_model.py	New abstract base class defining common interface & serialization.
src/rock_physics_open/equinor_utilities/machine_learning_utilities/exponential_model.py	Refactored to subclass BasePressureModel and simplified API.
src/rock_physics_open/equinor_utilities/machine_learning_utilities/sigmoidal_model.py	Rewritten as SigmoidalPressureModel based on BasePressureModel.
src/rock_physics_open/equinor_utilities/machine_learning_utilities/polynomial_model.py	New PolynomialPressureModel implementation.
src/rock_physics_open/equinor_utilities/machine_learning_utilities/friable_pressure_models.py	New friable bulk & shear pressure models.
src/rock_physics_open/equinor_utilities/machine_learning_utilities/patchy_cement_pressure_models.py	New patchy cement bulk & shear pressure models.
src/rock_physics_open/equinor_utilities/machine_learning_utilities/import_ml_models.py	Updated dynamic loader to recognize new model types.
src/rock_physics_open/equinor_utilities/machine_learning_utilities/init.py	Updated public exports to new model classes.

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