feat: implement pipeline feature for automated workflow steps

- Introduced a new pipeline service to manage custom workflow steps that execute after a feature is marked "In Progress".
- Added API endpoints for configuring, saving, adding, updating, deleting, and reordering pipeline steps.
- Enhanced the UI to support pipeline settings, including a dialog for managing steps and integration with the Kanban board.
- Updated the application state management to handle pipeline configurations per project.
- Implemented dynamic column generation in the Kanban board to display pipeline steps between "In Progress" and "Waiting Approval".
- Added documentation for the new pipeline feature, including usage instructions and configuration details.

This feature allows for a more structured workflow, enabling automated processes such as code reviews and testing after feature implementation.

apps/ui/src/components/views/board-view/dialogs/dependency-tree-dialog.tsx

@@ -131,7 +131,7 @@ export function DependencyTreeDialog({
                               : 'bg-muted text-muted-foreground'
                         )}
                       >
-                        {dep.status.replace(/_/g, ' ')}
+                        {(dep.status || 'backlog').replace(/_/g, ' ')}
                       </span>
                     </div>
                   </div>
@@ -177,7 +177,7 @@ export function DependencyTreeDialog({
                               : 'bg-muted text-muted-foreground'
                         )}
                       >
-                        {dependent.status.replace(/_/g, ' ')}
+                        {(dependent.status || 'backlog').replace(/_/g, ' ')}
                       </span>
                     </div>
                   </div>