Add Loop functionality to player controls

[adamantike]

Adding the Loop functionality, along with the Player changes to support it, and a button to the player controls.

Player now has a loopMode attribute, which determines whether it should loop. At the moment, only the following modes are supported:

• LoopNone: Disables loop.
• LoopAll: Enables loop for the entire playlist queue.

This has been designed as an enum, to support other modes in the future (e.g. loop for the current track only).

It depends on the loop functionality provided by MPV (using the loop-playlist option), so no custom logic is needed to reset the currently playing index.

[adamantike]

Thanks for tyding it up!

What do you think about adding icons similar to the following ones, which resemble what other apps use for this functionality?

• Repeat all: https://www.flaticon.com/free-icon/loop_5247950
• Repeat one: https://www.flaticon.com/free-icon/repeat_2284852

If you add them, I can use the one for the Repeat one, to implement that functionality.

[dweymouth]

Sounds good - I'll look for some SVG repeat icons with a compatible license and bundle them and let you know! I'm planning on releasing 0.4.0 soon, maybe later this week, once this plus the download completed notification @natilou was going to add, and the custom theme work I've been doing, are ready. I was planning on getting Jellyfin support into 0.4.0 initially, but that'll end up getting pushed back