feat(task-list): refine task list components and improve UI consistency

- Updated SubtaskLoadingSkeleton and TaskRow components for better spacing and visual consistency.
- Simplified TaskGroupHeader by removing unnecessary elements and enhancing the display of group names.
- Adjusted TaskListV2 to improve column rendering and added state management for field visibility synchronization with the database.
- Enhanced AddTaskRow and AddSubtaskRow components for improved user interaction and layout.
- Updated placeholder texts in CustomColumnComponents for better clarity.

worklenz-frontend/src/components/task-list-v2/TaskRowWithSubtasks.tsx

@@ -109,7 +109,7 @@ const AddSubtaskRow: React.FC<AddSubtaskRowProps> = memo(({
                   className="flex items-center gap-2 text-sm text-gray-500 dark:text-gray-400 hover:text-gray-700 dark:hover:text-gray-200 transition-colors h-full"
                 >
                   <PlusOutlined className="text-xs" />
-                  {t('addSubTaskText')}
+                  {t('addSubtaskText')}
                 </button>
               ) : (
                 <Input
@@ -121,7 +121,7 @@ const AddSubtaskRow: React.FC<AddSubtaskRowProps> = memo(({
                   className="w-full h-full border-none shadow-none bg-transparent"
                   style={{ 
                     height: '100%',
-                    minHeight: '42px',
+                    minHeight: '32px',
                     padding: '0',
                     fontSize: '14px'
                   }}
@@ -137,10 +137,12 @@ const AddSubtaskRow: React.FC<AddSubtaskRowProps> = memo(({
   }, [isAdding, subtaskName, handleAddSubtask, handleCancel, t]);
 
   return (
-    <div className="flex items-center min-w-max px-1 py-2 border-b border-gray-200 dark:border-gray-700 hover:bg-gray-50 dark:hover:bg-gray-800 min-h-[42px]">
-      {visibleColumns.map((column) =>
-        renderColumn(column.id, column.width)
-      )}
+    <div className="flex items-center min-w-max px-1 py-0.5 hover:bg-gray-50 dark:hover:bg-gray-800 min-h-[36px] border-b border-gray-200 dark:border-gray-700">
+      {visibleColumns.map((column, index) => (
+        <React.Fragment key={column.id}>
+          {renderColumn(column.id, column.width)}
+        </React.Fragment>
+      ))}
     </div>
   );
 });