The default `{{ TrackLink "https://listmonk.app" }}` template function
is clumsy to write and does breaks WYSIWYG editors and HTML syntax
highlighting because of the quotes. The new syntax doesn't break HTML
and is easier to write.
Eg: `<a href="https://listmonk.app@TrackLink">Link</a>`
- Introduce @TrackLink shorthand.
- Add first-class support for tracking links in the WYSIWYG (TinyMCE)
editor by introducing an on/off checkbox on the link dialog.
- Improve default dummy campaign content to highlight this.
- Change public and admin frontend primary colours.
- Change images.
- Refactor and fix styling on public pages.
- Remove CSS grid lib from public pages.
- Update Buefy and fix broken component styles (modal, toast).
