refactor tutorial structure and update for recent EDM4hep changes

[bndikt]

Summary

This PR performs a substantial cleanup and reorganization of the FCC SW tutorial documentation sources used to build the Sphinx documentation.

The changes are split into two main categories:

Documentation structure refactor

• Introduced a new chapter "Analysis at FCC" to isolate this tutorial section into a dedicated part of the documentation (previously part of 2. Generators, Fast Simulation and Analysis)
• Reorganized sections across chapters to improve the overall tutorial flow
• Cleaned up the underlying folder hierarchy for:
  • Markdown sources (.md)
  • Supporting Python scripts
  • Figures and assets
• Removed obsolete and unused files
• Restructured the repository layout to better reflect the final Sphinx-generated documentation structure

Content updates for recent EDM4hep changes

• Updated multiple tutorial pages to accommodate recent changes to EDM4hep
• Adapted example analysis scripts to regain compatibility between recent versions of FCCAnalyses and EDM4hep
• Generated new event data files with current version of SW stack, uploaded for users to download and run on

Motivation

The previous documentation structure had diverged from the logical structure presented in the generated Sphinx documentation, making maintenance and navigation increasingly difficult.

At the same time, recent EDM4hep updates introduced incompatibilities with newer FCCAnalysis releases, requiring updates across several tutorial sections.

This PR aims to improve:

• maintainability of the documentation sources,
• consistency of the tutorial organization,
• and compatibility with current FCC software tooling.

Notes

• This PR contains both structural refactoring and content updates.
• Some files may appear moved/renamed due to the repository reorganization.
• Note: Many sections remain to be updated to properly reflect the changes to edm4hep