Attach note to a Project (or File)

Is your feature request related to a problem? Please describe.
I write a note, which pertains to a particular file or folder on the filesystem. I'd like to be able to attach, or associate, this note to the file / folder in some simple and direct way while writing.

Describe the solution you'd like
Perhaps this might become possible through #331 and Nextcloud Text implementation. Could also involve one of the options below...

Describe alternatives you've considered

• Browse to the /notes/mynote.txt location on the hard drive and save a copy of the note in a nearby directory or something.
• Browse to the /notes/mynote.txt location on the hard drive and leave a comment.
• #74 is support for attachments in notes. This approach is a bit different: to write the note and then attach it to something else on the file system.
• System wide tagging could expand note tags in the future.
• Projects functionality might eventually relate to this.

Start by reviewing issue #331 and the referenced Nextcloud Text implementation, then compare the attachment approach in issue #74 and the Projects functionality mentioned here. The issue would be complete only after the association model and user-facing behavior are defined and implemented.