feat: implement comprehensive task management system with SCSS modules

- Add complete task management functionality with atomic design
- Create TaskCard component with checkbox and delete functionality
- Implement TaskForm with drawer interface for task editing
- Add Tasks organism with right-side drawer and completion states
- Move TodayProgress and QuickActions to Sidebar for better UX
- Implement SCSS modules for all components with proper styling
- Add task statistics to progress tracking
- Update store with task management actions and persistence
- Improve layout with 30/70 column split for tasks and timer
- Add SASS dependency for SCSS compilation
- Ensure completed tasks are non-editable with proper visual states

package.json

@@ -99,6 +99,7 @@
     "drizzle-kit": "^0.30.4",
     "esbuild": "^0.25.0",
     "postcss": "^8.4.47",
+    "sass": "^1.92.0",
     "tailwindcss": "^3.4.17",
     "tsx": "^4.19.1",
     "typescript": "5.6.3",