feat: add swimlane mode selection to KanbanFilters and BoardContainer

- Introduced `swimlanesMode` in `KanbanFilters` to toggle between 'tags' and 'priority' swimlanes.
- Updated `KanbanBoardContainer` to conditionally render `PrioritySwimlanesBoard` based on the selected mode.
- Enhanced UI to include dropdown for swimlane mode selection, improving user experience in task organization.
- Adjusted `TasksContext` to persist swimlane mode preferences, ensuring consistent behavior across sessions.

services/user-preferences.ts

@@ -12,6 +12,7 @@ export interface KanbanFilters {
 export interface ViewPreferences {
   compactView: boolean;
   swimlanesByTags: boolean;
+  swimlanesMode?: 'tags' | 'priority';
   showObjectives: boolean;
 }