Add `html-manual` Meson option to allow building manpages without the
HTML manual, removing the mdbook dependency for manpage-only builds.
Changes:
- Add `html-manual` Meson option (default: true)
- Make HTML manual build conditional in meson.build
- Add `buildHtmlManual` parameter to package.nix
- Conditional outputs: ["out" "man"] when enabled, ["out"] when disabled
- Make mdbook/rsync/json-schema-for-humans dependencies conditional
- Add `nix-manual-manpages-only` package variant
This allows systems that only need manpages to avoid the mdbook build
dependency while preserving full functionality for HTML manual builds.
Add configurable documentation URLs that change based on whether this is
an official release or development build:
- Nix builds:
- Development (officialRelease = false): Use /latest/ URLs
- Official releases (officialRelease = true): Use versioned URLs with
MAJOR.MINOR only (e.g., /2.33/ instead of /2.33.0/)
- Plain meson builds: Default to versioned URLs (official-release = true)
Changes:
- Add --doc-url parameter to expand-includes.py
- Add meson option 'official-release' (defaults to true for Meson builds)
- Compute doc_url in meson.build based on version and official-release
- Forward Nix officialRelease variable to Meson in package.nix
- Update render-manpage.sh to pass doc-url parameter
This allows distros (Fedora, etc.) to have stable versioned URLs by default,
while Nix development builds point to /latest/ for up-to-date documentation.