Revamp the existing translation system, simplifying
management and adding several new languages. The new system reads from
TOML files in the `/i18n` directory and improves template structures.
It also enhances customisation options and robustness by providing
fallbacks and modularity.
- Implement a new, streamlined translation macro.
- Load translations from `/i18n` TOML files.
- Remove redundant configuration requirements.
- Refactor templates to align with new i18n system.
- Add support for Hindi, Japanese, Russian, Portuguese, Chinese,
Italian, German, Ukranian, Korean, and French languages.
- Credit Thomas Weitzel (@thomasweitzel) for inspiration.
- Introduce `toc_ignore_pattern` to ignore specific headers based on regex.
- Allow custom ToC placement with shortcode or "<!-- toc -->" marker.
- Increase max depth for ToC to 4.
- Update Documentation for the above features.
- Move ToC generation to a macro file.
Used as fallback when JS is disabled and `theme_switcher` is enabled.
If `default_theme` is unset, it defaults to "light".
Used as single theme when `theme_switcher` is disabled.
