Enhance documentation and automation workflows

[eleanorfrajka]

Enhance documentation organization and add modern automation workflows for better maintainability.

Tasks:

• Set up API documentation generation
• Add automated changelog generation (towncrier)
• Include dependency update automation (dependabot)

References:

• https://www.pyopensci.org/python-package-guide/
• See MODERNIZATION_PLAN.md#7-documentation-structure