feat(drive): remove create_home_folder

remove create_home_folder() & ensure_home_folder()

    now: on_user_created() and on_user_login both() call provision_if_needed()
    which calls **create_personal_drive_atomic()**

    add a helper to find Personal drive for a user and also it's root directorry

src/application/services/share_service.rs

@@ -1034,15 +1034,6 @@ mod tests {
         async fn delete_folder_permanently(&self, _folder_id: &str) -> Result<(), DomainError> {
             unimplemented!()
         }
-
-        async fn create_home_folder(
-            &self,
-            _user_id: Uuid,
-            _drive_id: Uuid,
-            _name: String,
-        ) -> Result<crate::domain::entities::folder::Folder, DomainError> {
-            unimplemented!()
-        }
     }
 
     struct MockShareRepository {