chore: build docs from single-source community files

[lschilders]

This pull request streamlines how community documents (like the Code of Conduct and Contributing Guide) are integrated into the documentation and improves cross-referencing and navigation within the docs. The main changes involve removing duplicated Markdown files from the repository, updating the Sphinx configuration to better handle included Markdown, and simplifying the documentation source files to include the community files from a single source of truth.

Community file management and documentation integration:

• Removed the duplicated .github/CODE_OF_CONDUCT.md and .github/CONTRIBUTING.md files from the repository, ensuring these are now materialized into the docs at build time from the org-level OpenSTEF/.github repository, and included in the documentation via the _community/ directory. [1] [2]
• Updated docs/source/contribute/code_of_conduct.rst and docs/source/contribute/contributing_guide.rst to include the respective Markdown files from _community/ using the MyST parser, rather than maintaining separate RST content. [1] [2]

Sphinx documentation build improvements:

• Added and configured the sphinx.ext.autosectionlabel extension in docs/source/conf.py to automatically generate unique cross-reference labels for every section heading, making it easier to deep-link into included Markdown documents. Also, configured Sphinx to suppress duplicate label warnings and to exclude _community/ files from source discovery. [1] [2] [3]
• Enabled automatic anchor generation for Markdown headings (h1-h4) with myst_heading_anchors = 4 in docs/source/conf.py, ensuring intra-page links in included Markdown files work as expected.

Documentation navigation and linking updates:

• Updated links in docs/source/contribute/index.rst to use the new autosectionlabel-prefixed section references, ensuring that navigation cards and references point to the correct sections in the included community documents. [1] [2]

[egordm]

Looks good. Maybe recheck if files already exist would be nice. Otherwise approved.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud