Adds the ability to add a track and cycle through the
tracks from player widget. Also displays the current track
being played or edited in a dropdown that allows
for quick track selection.
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
