feat(task-management): enhance task grouping and localization support

- Implemented unmapped task grouping for better organization of tasks without valid phases.
- Updated task distribution logic to handle unmapped tasks and added a corresponding group in the response.
- Enhanced localization by adding translations for "noTasksInGroup" in multiple languages.
- Improved task list components to support custom columns and better task management features.
- Refactored task management slice to include loading states for columns and custom columns.

worklenz-frontend/src/features/task-management/taskListFields.slice.ts

@@ -59,13 +59,21 @@ const taskListFieldsSlice = createSlice({
       const field = state.find(f => f.key === action.payload);
       if (field) {
         field.visible = !field.visible;
+        // Save to localStorage immediately after toggle
+        saveFields(state);
       }
     },
     setFields(state, action: PayloadAction<TaskListField[]>) {
-      return action.payload;
+      const newState = action.payload;
+      // Save to localStorage when fields are set
+      saveFields(newState);
+      return newState;
     },
     resetFields() {
-      return DEFAULT_FIELDS;
+      const defaultFields = DEFAULT_FIELDS;
+      // Save to localStorage when fields are reset
+      saveFields(defaultFields);
+      return defaultFields;
     },
   },
 });