Add workflow success edge (#10120)

- Refactor the handles: the source handles are now part of the edges as
markerStart
- **As the source handles are now part of the edges, we can delete the
`markLeafNodes` logic; this can be done in another PR**. See
https://github.com/twentyhq/core-team-issues/issues/386
- Create a custom edge component for the default edge
- Create a custom edge component for the success edge; this includes a
label

**The edges can be tested in Storybook. I wrote two stories for the
edges.**

| Default | Success |
|--------|--------|
| ![CleanShot 2025-02-11 at 11 46
09@2x](https://github.com/user-attachments/assets/c7c42328-6502-4c77-bdc9-dea825d4651a)
| ![CleanShot 2025-02-11 at 11 46
16@2x](https://github.com/user-attachments/assets/572204de-299c-4cbc-9900-46744b59c351)
|

packages/twenty-e2e-testing/tests/workflow-creation.spec.ts

@@ -28,7 +28,9 @@ test('Create workflow', async ({ page }) => {
 
   const nameInput = page.getByRole('textbox');
   await nameInput.fill(NEW_WORKFLOW_NAME);
-  await nameInput.press('Enter');
+
+  const workflowDiagramContainer = page.locator('.react-flow__renderer');
+  await workflowDiagramContainer.click();
 
   const body = await createWorkflowResponse.json();
   const newWorkflowId = body.data.createWorkflow.id;