feat: implement label management with color filtering

CHANGELOG.md

@@ -4,6 +4,14 @@ All notable changes to this project will be documented in this file.
 
 ## [Unreleased] - 2026-01-04
 
+### Added
+- **Label Management System**: Complete redesign of label/tag management
+  - Added `Label` model to Prisma schema with centralized database storage
+  - Created `LabelContext` for global state management with React Context API
+  - Added `useLabels` hook for easy access to label functionality
+  - Implemented full CRUD API for labels (GET, POST, PUT, DELETE)
+  - Updated all components to use the new context instead of localStorage
+
 ### Fixed
 - **Tests**: Fixed Playwright drag-and-drop tests to work with dynamically generated note IDs
   - Changed selectors from hardcoded text (`text=Note 1`) to flexible attribute selectors (`[data-draggable="true"]`)
@@ -11,13 +19,22 @@ All notable changes to this project will be documented in this file.
   - Replaced UI-based cleanup with API-based cleanup using `request.delete()` for more reliable test cleanup
 
 ### Database
-- Cleaned up 38 accumulated test notes from the database using MCP memento tool
+- Cleaned up 38 accumulated test notes from database using MCP memento tool
 - Retained only essential notes: "test" and 2x "New AI Framework Released"
+- Added migration `20260104203746_add_labels_table` for new Label model
 
 ### Technical Details
-- The drag-and-drop functionality itself was working correctly
-- The issue was in the Playwright tests which expected exact text matches but notes were created with unique IDs (e.g., `test-1767557327567-Note 1`)
-- Tests now properly handle the dynamic note generation system
+- **Label Management**: 
+  - Labels now stored in database with colors, eliminating localStorage duplication
+  - All label operations are centralized through LabelContext
+  - Automatic synchronization across all components
+  - Better performance with single source of truth
+  - Support for user-specific labels (userId field for future auth)
+  
+- **Tests**: 
+  - The drag-and-drop functionality itself was working correctly
+  - The issue was in Playwright tests which expected exact text matches but notes were created with unique IDs (e.g., `test-1767557327567-Note 1`)
+  - Tests now properly handle the dynamic note generation system
 
 ## [Previous Versions]