Issue note email should include link to comment in header

Problem to solve

Currently emails for notes/comments on issues have the following layout:

Clicking on the dots shows the footer:

The problem is that the view it on GitLab link in the footer is usually the only piece of information in the email I care about, since I prefer reading comments in the context of the issue. (The email thread may not have all context or have in the wrong order for threaded comments).

You could argue that Gmail shouldn't fold the footer, but then again, I'd say the link to the comment should be in the header anyway. Currently I click the Author link about half the time when I get such an email, only then realizing this is not the link I wanted. (While knowing the author is useful, linking it is not really that useful.)

Also, it might be nice to have the issue title here as well because in long email threads the subject of the email can be off the screen.

TL;DR: The email header should contain a link to the comment and/or issue, and maybe the issue name as well.

Proposal

The email header could look something like:

This is probably too many links in one line, but note that the commented link is the most important one so this would work as well:

Author commented on issue #1 test:

Code

Change this file to have:

  = succeed ':' do
    = link_to note.author_name, user_url(note.author)
    - if discussion.nil?
      = link_to 'commented', target_url
      on ##{issue.iid}
      = link_to(issue.title, issue)
    - else
      - if note.start_of_discussion?
        started a new
      - else
        commented on a

      - if discussion&.diff_discussion?
        discussion on #{link_to(discussion.file_path, target_url)}
      - else
        = link_to 'discussion', target_url