Defines a common interface for music backends with publishers for playback state, artwork, and control commands, plus capability flags for volume and favorite support. This allows MusicManager to switch between Apple Music, Spotify, YouTube Music, and NowPlaying controllers without changing UI code. The protocol is self-contained and could be extracted into any Swift media client that needs multi-backend support.

Provides image processing operations including background removal via the Vision framework, format conversion between PNG/JPEG/HEIC/TIFF/BMP, and PDF creation. It is isolated from the notch-specific UI and can be reused in any macOS or iOS image-manipulation project with minimal adaptation.

Client for the embedded non-sandboxed XPC helper service that performs privileged operations such as brightness and keyboard backlight control. It demonstrates a clean separation between a sandboxed host app and an elevated helper, and serves as a reusable template for macOS applications needing entitlement-limited privileged operations.

Encapsulates AppleScript command execution for controlling media applications, with error handling and higher-level wrappers for playback commands. This is a reusable utility for any macOS app that needs Apple Events automation, especially for Spotify and Apple Music integration.