This commit updates the Jekyll configuration file (`_config.yml`) to:
- Include `README.md` and `CHANGELOG.md` in the site build.
- Exclude `CONTRIBUTING.md` and `CLAUDE.md` from the site build.
This commit updates the Jekyll configuration to include `jekyll-github-metadata` and `jemoji` plugins. It also introduces a `CHANGELOG.md` file that automatically generates a formatted changelog page from GitHub releases. The default changelog text for new app versions in Fastlane has also been updated to be more engaging and directly link to the new changelog page.