📝 Add SSE refactoring plan

changelog.md

@@ -1278,4 +1278,10 @@ Added SSE endpoint to UI server:
 - Added /sse endpoint for real-time updates
 - Implemented page-specific event channels using Watermill
 - Added CORS support for cross-origin requests
-- Added proper error handling and connection management
+- Added proper error handling and connection management
+
+Created refactoring plan for SSE implementation:
+- Designed modular event system with dedicated packages
+- Planned separation of Watermill integration
+- Created detailed implementation steps for SSE handler
+- Added comprehensive testing and documentation plan