Merge latest changes

[Jorgelmh]

This pull request introduces several improvements and updates across the codebase, focusing on enhancing FMU example configurations, updating Python version support in CI workflows, and refactoring example models for clarity and flexibility. The most important changes are grouped below by theme.

Continuous Integration and Python Version Updates:

• Added support for Python 3.13 to the main test workflow and updated the future/experimental workflow to test against Python 3.14 instead of 3.13. This ensures ongoing compatibility with the latest Python releases. [1] [2] [3]
• Standardized the installation of test dependencies in CI workflows by switching --extra modelTest to --extra tests for consistency. [1] [2] [3]

FMU Example and XML Structure Enhancements:

• Improved and expanded example FMU XML structures: added new examples (BouncingBallStructure.xml, ForcedOscillator6D.xml), enhanced existing ones with algorithm and ECCO configuration sections, and clarified variable connections and causality. [1] [2] [3] [4]

Component Model and Documentation Improvements:

• Added a new documentation file, component-development-process.rst, providing a step-by-step guideline for developing FMUs using the component-model approach, including best practices and explanations of virtual derivatives.
• Refactored the driving_force_fmu.py example to support vectorized amplitudes, frequencies, and frequency sweeps, improved type annotations, and clarified variable initialization, making the model more flexible and robust. [1] [2] [3]

Other Notable Changes:

• Updated the range for the height variable in bouncing_ball_3d.py to use inches instead of meters for the upper bound, improving unit clarity.
• Removed the obsolete new_pythonfmu_features.py example, cleaning up the examples directory.
• Minor internal code and type hinting improvements in documentation extension scripts.

These changes collectively modernize the project, improve testing and documentation, and enhance the flexibility and clarity of example models.