Per-timeline notification option

[schulle4u]

As the title suggests, I would like to be able to enable notifications for all timelines, not just mentions. Since it is already possible to set notifications to 'sound only', it would be nice to have a subtle background sound for the home timeline, so that you don't completely forget about Mastodon while you're working. 🙂

[trypsynth]

Not sure if I want this, to be honest. I mean I can always add it and then just not use it, but it sorta goes against the spirit of Fedra, a light-weight, distraction free social media experience. I'll consider it, and welcome input from others.