[Self-Hosted] New users without birthday collection in registration are treated as children

Possibly related to #815, new users are unable to make changes to the privacy settings and (as far as I can tell) there's nowhere to verify age / update the birthdate.

Stable Web 2026.929.141640

In the browser network tab you'll see PATCH request to /settings {"sensitive_content_friend_dm_filter":0,"sensitive_content_non_friend_dm_filter":0,"sensitive_content_guild_filter":1} returns {"code":"VALIDATION_ERROR","message":"Validation failed.","errors":[{"path":"sensitive_content_friend_dm_filter","code":"AGE_RESTRICTED","message":"Non-adult users can only set friend DM filter to blur or block"}]} Manually setting the users' date of birth in the /admin panel allows this to save correctly. The AGE_VERIFIED_ADULT and VERIFIED_NOT_UNDERAGE flags have no effect on this.