[User Story] - As a user, I want to add, edit, and delete columns within a table (Sheet) so that I can customize the data structure to fit my needs.

[ichirokentaro]

User Story:

• As a user, I want to add, edit, and delete columns within a table (Sheet) so that I can customize the data structure to fit my needs.

Acceptance Criteria:

1. Add Column:

   • Given I am viewing a Sheet, when I click the "Add Column" button, then I should see a prompt or form to enter the name and type of the new column.
   • Given I have entered a name and selected a type for the new column, when I click the "Add" button, then the new column should be created and added to the Sheet.
   • Given I have successfully added a new column, when I view the Sheet, then I should see the newly created column with the specified name and type.

2. Edit Column:

   • Given I am viewing a Sheet, when I select a column and click the "Edit Column" option, then I should see a prompt or form to edit the name and type of the column.
   • Given I have entered a new name or changed the type for the column, when I confirm the edit action, then the column should be updated with the new name and type.
   • Given I have successfully edited a column, when I view the Sheet, then I should see the column with the updated name and type.

3. Delete Column:

   • Given I am viewing a Sheet, when I select a column and click the "Delete Column" option, then I should see a confirmation prompt asking if I am sure I want to delete the column.
   • Given I have confirmed the deletion, when I proceed with the delete action, then the selected column should be removed from the Sheet.
   • Given I have successfully deleted a column, when I view the Sheet, then I should no longer see the deleted column.

4. User Feedback:

   • Given I have added, edited, or deleted a column, when the action is completed, then I should receive a confirmation message or notification indicating the successful completion of the action.

5. Validation for Column Name:

   • Given I am adding or editing a column, when I enter a name, then the system should validate that the name is not empty and does not duplicate an existing column name within the same Sheet.
   • Given I have entered an invalid name for a column, when I try to add or edit the column, then I should see an error message indicating the problem.