Improve MacOS support

[0SkillAllLuck]

Add proper MacOS support including the following improvements:

• Use MacOS specific icons to improve the native feeling
• Integrate with "playing now"
• Proper media controls in the player
• Proper main menu (using the menu bar instead of a menu inside the app)
• Fix audio playback not working
• Fix constant keychain pop-ups
• Fix duplicate libgio loading (one from bundle, one from nix store)

[0SkillAllLuck]

The playing now will be fixed with: #99

[0SkillAllLuck]

Fix the icons on MacOS with: #100

[0SkillAllLuck]

Fix playing now integration with: #99

[0SkillAllLuck]

Fix duplicate libgio with: #101

[0SkillAllLuck]

Fix the keychain popups: #102