Implement documentation website

[stuitje]

PR Summary

This PR implements the first version of documentation for SOCRATES, using Zensical and an mkdocs configuration style, in the same style as proteus. It is not complete yet and will be updated soon. Main added pages:

• Landing page with a quick overview of socrates and its role in proteus
• Model overview in Explanations, adapted from the technical guide, in three pages
• explanation of the spectral file use and structure, now still taken from technical guide, but will be adapted later to have proteus-specific info
• Overview of integration into proteus, focuses on AGNI
• two reference pages on the spectral files, one for the standard MET office files and one for the PROTEUS ones, taken from the PDF available in proteus
• community pages (contact, code of conduct)
• proteus framework landing page to link to other modules
• installation guide which is still empty, but refers to installation in proteus, agni and janus

It misses most notably a full installation guide and tutorial, publications, and a getting started page which will be added soon (after I am back from holiday)

Code Quality Checklist

• I have performed a self-review of my own code
• My code follows the project's style guidelines
• Comments have been included that aid undertanding and enhance the
  readability of the code
• My changes generate no new warnings

AI Assistance and Attribution

• Some of the content of this change has been produced with the assistance
  of Claude Sonnet 4.6, and I have followed the AI guidelines in the PROTEUS documentation.

Documentation

• Where appropriate I have updated documentation related to this change and
  confirmed that it builds correctly

Sci/Tech Review

• I understand this area of code and the changes being added
• The proposed changes correspond to the pull request description
• Documentation is sufficient (do documentation papers need updating)
• Sufficient testing has been completed

Please alert the code reviewer via a tag when you have approved the SR

Code Review

• All dependencies have been resolved
• Related Issues have been properly linked and addressed
• CLA compliance has been confirmed
• Code quality standards have been met
• Tests are adequate and have passed
• Documentation is complete and accurate
• Security considerations have been addressed
• Performance impact is acceptable

[Copilot]

Pull request overview

This PR introduces an initial MkDocs-based documentation website for the SOCRATES codebase, including site navigation, theming/custom assets, and a GitHub Pages deployment workflow.

Changes:

• Add MkDocs configuration (mkdocs.yml) with initial docs IA (Home / How-to / Explanations / Reference / Community).
• Add custom Material theme styling + overrides (CSS, JS, template override) and documentation content pages.
• Add a GitHub Actions workflow to build and deploy the docs to GitHub Pages, plus ignore the generated site/ output.

Reviewed changes

Copilot reviewed 20 out of 31 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
mkdocs.yml	Defines MkDocs/Material configuration and site navigation for the new docs site
docs/index.md	Adds a landing page describing SOCRATES and its PROTEUS/AGNI context
docs/How-to/installation.md	Adds a placeholder installation page linking to external install docs
docs/Explanations/*.md	Adds initial explanatory documentation pages (two-stream, spherical harmonic, spectral files, interface, integration, overview)
docs/Reference/*.md	Adds reference pages for standard Met Office and PROTEUS spectral files
docs/Community/*.md	Adds community pages (contact + code of conduct)
docs/stylesheets/*.css	Adds theme CSS for PROTEUS-style branding and footnote/subtitle tweaks
docs/overrides/main.html	Adds a template override to manage theme-dependent favicons
docs/javascripts/header-links.js	Adds header click behavior for logo/title navigation
docs/assets/*.png	Adds logo and schematic image assets used by the site
.github/workflows/docs.yaml	Adds GitHub Pages deployment workflow for the documentation
.gitignore	Ignores generated MkDocs site output directory (site/)

[nichollsh]

Very nice - great to have some documentation for SOCRATES! Some suggestions/corrections below.

Next, it would be great if the LaTeX-built techguide and userguide PDFs could be embedded or referenced in the website, by drawing these straight from GitHub actions (see comment below).