Deleting a course fails to update the meilisearch index

[AntonOfTheWoods]

Deleting a course via the django command delete_course fails the meili part with:

`Attribute `course` is not filterable. Available filterable attribute patterns are: `catalog_visibility`, `enrollment_end`, `language`, `modes`, `org`.`

The course no longer appears in authoring but does still appear in https://{LMS}/courses.

Adding content to INDEX_FILTERABLES for course_info seems to fix the issue.

The stacktrace:

...
Are you sure you want to delete course course-v1:badorg+badcn+badcr? [y/N] y                                                                     
Are you sure? This action cannot be undone! [y/N] y                                                                                              
2025-10-25 09:38:08,145 INFO 75 [xmodule.modulestore.split_mongo.split] [user None] [ip None] split.py:2610 - deleting course from split-mongo: c
ourse-v1:badorg+badcn+badcr                                                                                                                      
2025-10-25 09:38:08,168 INFO 75 [search.meilisearch] [user None] [ip None] meilisearch.py:195 - Search query: opt_params={'showRankingScore': Tru
e, 'filter': ['course = "course-v1:badorg+badcn+badcr"', 'org = "badorg"']}                                                                      
2025-10-25 09:38:08,190 ERROR 75 [django.dispatch] [user None] [ip None] dispatcher.py:264 - Error calling listen_for_course_delete in Signal.sen
d_robust() (MeilisearchApiError. Error code: invalid_search_filter. Error message: Index `tutor_course_info`: Attribute `course` is not filterable. Available filterable attribute patterns are: `catalog_visibility`, `enrollment_end`, `language`, `modes`, `org`.                              
1:7 course = "course-v1:badorg+badcn+badcr". Hint: It might not be working because you're not up to date with the Meilisearch version that search
 call requires. Error documentation: https://docs.meilisearch.com/errors#invalid_search_filter Error type: invalid_request)                      
Traceback (most recent call last):                                                                                                               
  File "/openedx/venv/lib/python3.11/site-packages/meilisearch/_httprequests.py", line 224, in __validate                                        
    request.raise_for_status()                                                                                                                   
  File "/openedx/venv/lib/python3.11/site-packages/requests/models.py", line 1026, in raise_for_status
    raise HTTPError(http_error_msg, response=self)                                                                                               
requests.exceptions.HTTPError: 400 Client Error: Bad Request for url: http://meilisearch:7700/indexes/tutor_course_info/search
...