Fix/player state - Githubissues

Description

Adds on_wavelink_node_disconnected and player.switch_state. Fixes some disconnect state logic.

Has been tested on a few bots and afaik there are no issues.

[x] If code changes were made then they have been tested.
- [x] I have updated the documentation to reflect the changes.
- [ ] I have updated the changelog with a quick recap of my changes.
[x] This PR fixes an issue.
[x] This PR adds something new (e.g. new method or parameters).
[ ] This PR is a breaking change (e.g. methods or parameters removed/renamed)
[ ] This PR is not a code change (e.g. documentation, README, ...)
[x] I have read and agree to the Developer Certificate of Origin for this contribution