Bounce dock only once on receiving a private message

[kanishk98]

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What's this PR do?

1. Changes dock badge on macOS from a dot to the unread PM count of the server that last received a PM.
2. Makes dock bounce only once (as opposed to every time the favicon of the web app is updated)

Any background context you want to provide?

Check out the discussion here.
Server repo PR here.

Screenshots?

You have tested this PR on:

• Windows
• Linux/Ubuntu
• macOS

[kanishk98]

@akashnimare I'll update this PR based on Tim's response in the server-side repo issues. Shouldn't take more than 10-15 minutes once we confirm that this is required. Hope that's not a problem.

[kanishk98]

After our discussion in #12222, I think we're confident of going ahead with this feature. I've updated the PR. It'll be great if someone can test it out on a Mac on their end and let me know if there are any problems.

[akashnimare]

@kanishk98 can you fix the merge conflicts? Also, we agreed to merge #12222, right?

[kanishk98]

can you fix the merge conflicts?

Fixed those. :)

Also, we agreed to merge #12222, right?

Yeah, we'd agreed that the server-side notifications page wasn't enough to handle the specific Mac dock bounce issue. I think Tim and Rishi just wanted to wait till we integrated notifications settings into the desktop app. We've done that now, so should be good to merge both these PRs.

[zulipbot]

Heads up @kanishk98, we just merged some commits that conflict with the changes your made in this pull request! You can review this repository's recent commits to see where the conflicts occur. Please rebase your feature branch against the upstream/master branch and resolve your pull request's merge conflicts accordingly.