This pull request migrates the notification system in the shared Kotlin Multiplatform (KMP) core from the old MeshServiceNotifications to a new, unified NotificationManager abstraction. This enables consistent, cross-platform notification handling for both Android and Desktop, and updates all relevant usages in the core data layer.

The most important changes are:

New Feature Tracks and Documentation:

• Added a new track for Desktop UX Enhancements, including a specification, phased implementation plan, and metadata describing goals such as tray integration, notifications, window state persistence, and menu bar/shortcut support. [1] [2] [3] [4]
• Added a new track for Wire Up Notifications, with a detailed specification, phased plan, and metadata for implementing a unified, cross-platform notification system in KMP. [1] [2] [3] [4]

Notification System Refactor (Core Data Layer):

• Replaced all usages of MeshServiceNotifications with the new NotificationManager abstraction throughout the core data managers (MeshDataHandlerImpl, FromRadioPacketHandlerImpl, MeshActionHandlerImpl, etc.), ensuring all notification dispatches now use the unified interface. [1] [2] [3] [4] [5] [6] [7] [8] [9] [10]
• Refactored notification logic for client notifications, low battery, alerts, and waypoint events to use the new NotificationManager.dispatch() method with structured notification data, including title, message, category, and other relevant fields. [1] [2] [3] [4]

Product Documentation Update:

• Updated the product documentation to highlight unified, cross-platform notifications as a core feature.