As a user, I want to export my notes to different formats (e.g., PDF, Markdown) so that I can back them up or use them outside the app

[BrigitaKasemets]

• [ ] There is an "Export" option for each note.
• [ ] You can convert notes into PDF file format.
• [ ] Users can download the exported file.

[BrigitaKasemets]

[henno]

Convert this list of commands to a list criteria

[henno]

Start with just one format to keep story size under control.