v0.0.15

Journal Plugin Enhancements

• Added support for managing additional_metadata.
• Implemented link validation with a corresponding "last checked" date.
• Used file creation date as a fallback when no explicit date is provided.
• Added support for multiple folders in the Journal plugin.

List Subfolder Plugin

• Introduced support for handling multiple folders.

Build Improvements

• Added the mkdocs-exclude plugin to the Dockerfile.