Remove cursor summary from generated changelog (tldraw#7142)

see title

### Change type

- [x] `other`

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Stops including <!-- CURSOR_SUMMARY --> sections when generating the
draft changelog.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
fbfa8d7. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

Author: ds300

internal/scripts/extract-draft-changelog.tsx

@@ -140,6 +140,8 @@ export async function extractChangelog(startRef: string, endRef: string): Promis
 
 		// Remove the Change type section and all checkboxes
 		restOfMessage = restOfMessage
+			// remove cursor summary
+			.replace(/<!-- CURSOR_SUMMARY -->(.|\s)*/gm, '')
 			// remove Change type section
 			.replace(/### Change type[\s\n]*/g, '')
 			// remove checkboxes