chore: Updating hooks docs for v3

markdown/dev/reference/api/hooks/postpartdraft/en.md

@@ -0,0 +1,27 @@
+---
+title: postPartDraft
+---
+
+The `postPartDraft` lifecycle hook runs just after a part is drafted.
+It will fire once for each part in each set (of settings).
+
+## Signature
+
+```js
+null hook(Pattern pattern)
+```
+
+## Example
+
+```js
+pattern.on('postPartDraft', pattern => {
+  // Mutate the pattern object here
+  // You can use the pattern.activePart 
+  // and pattern.activeSet properties to
+  // figure out for which part this hook was fired
+}
+```
+
+## Notes
+
+The `postPartDraft` hook is rarely used, but it's there if you need it.