Harden site link resolution for GitHub Pages

[OgeonX-Ai]

Motivation

• Fix broken internal navigation and search links when the static site is served from the docs/ root or from subpages under docs/pages/ on GitHub Pages.
• Provide a single, robust way to compute a stable base path that handles trailing slashes and index.html variants.
• Centralize path resolution logic in the site script to prevent future relative-path regressions.

Description

• Added a complete documentation/site scaffold (multiple docs/* markdown files, docs/pages/* HTML pages, docs/assets/style.css, docs/assets/app.js, CI and GitHub templates) to provide a browsable static site and canonical docs.
• Updated docs/assets/app.js to introduce getBasePath() and replace the previous simple resolver with resolveHref(targetPath) that trims trailing slashes, strips /index.html, and handles /pages/ segments to compute a stable base path.
• Ensured navigation and search builders (buildNav() and setupSearch()) use the new resolveHref() so links resolve correctly from both the site root and subpages.
• Kept the site lightweight (no external deps) and added an index.html and per-page HTML under docs/pages/ to validate the behavior.

Testing

• Started a local server with python -m http.server 8000 and verified http://127.0.0.1:8000/index.html served correctly.
• Ran a Playwright script to load the index page and capture a screenshot which completed and produced artifacts/docs-site-index-fixed.png, confirming rendered navigation.
• Both the server check and the Playwright run succeeded.
• Repository CI (.github/workflows/ci.yml) was added but was not executed as part of this change.

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Codex Task