Prepare for separate steps for each simulator

[kmichalikk]

This PR prepares the user docs to contain separate steps for each simulator. Additionally, it mentiones Geant4 as a simulator available in Demo Mode, and adds some mkdocs extensions for more rich user documentation.

With the extension, we are able to render better-looking Admonitions:

Example of a tabbed part of the doc:

For now, other simulators are "Under development":

[Copilot]

Pull Request Overview

This PR enhances the user documentation by restructuring it to provide simulator-specific instructions for SHIELD-HIT12A, FLUKA, and Geant4. It also upgrades the documentation framework by adding MkDocs extensions for better presentation.

• Adds markdown extensions (admonition, pymdownx.details, pymdownx.superfences, pymdownx.tabbed) for richer documentation formatting
• Restructures tutorial content into tabbed sections for each simulator
• Updates references to include Geant4 as available in Demo Mode

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 8 comments.

Show a summary per file

File	Description
mkdocs.yml	Adds markdown extensions for admonitions, details, superfences, and tabbed content
docs/index.md	Updates platform description to mention all three simulators and clarifies Demo Mode capabilities
docs/geometry.md	Converts existing geometry tutorial into tabbed format with simulator-specific sections
docs/settings.md	Restructures beam and physics settings documentation with tabs for different simulators
docs/scoring.md	Organizes scoring instructions into simulator-specific tabs with improved formatting
docs/running.md	Reorganizes simulation running instructions with tabs and info admonitions

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