chore(migration): add obj flags migration script (#10380)

Co-authored-by: Akos Vandra-Meyer <axos88@users.noreply.github.com>

docs/src/changelog/migration-v10.mdx

@@ -399,7 +399,14 @@ if you need finer control.
   bool h = lv_obj_is_hidden(obj);
   ```
   The custom-bit flags (`LV_OBJ_FLAG_USER_1`–`4`) can be accessed via
-  `lv_obj_set/get_user_flag()`
+  `lv_obj_set/get_user_flag()`, which take a bit from 0 to 3 e.g `lv_obj_set_user_flag(obj, 0, true)`
+  instead of lv_obj_get/set-flag(obj, LV_OBJ_FLAG_USER_1).
+
+  A migration script is available at `scripts/migration/migrate_obj_flags.py`:
+  ```bash
+  	python3 scripts/migration/migrate_obj_flags.py path/to/your/project
+  ```
+  _Note: Only raw flag constants can be converted automatically. Expressions using variables will be skipped for safety._
 
 ---
 

docs/src/common-widget-features/flags.mdx

@@ -8,7 +8,8 @@ Flags are deprecated in LVGL v9.6 and will be removed in LVGL v10.
 Use a dedicated function instead, such as <ApiLink name="lv_obj_set_hidden"/>.
 
 <ApiLink name="lv_obj_set_user_flag"/> and <ApiLink name="lv_obj_get_user_flag"/>
-can be used to replace `LV_OBJ_FLAG_USER_1-4`.
+can be used to replace `LV_OBJ_FLAG_USER_1-4`, it takes in a bit from 0 to 3 instead 
+of the old flag constant, e.g `lv_obj_set_user_flag(obj, 0, true)`
 </Callout>
 
 Some widget attributes can be enabled or disabled using