[DATABASE] Enable fulltext search by default

Also rename fulltext indices to more fitting names

Imported from v2/f84dbb369f01a1d4a9bc362d01cdd100cdc79313

src/Entity/Activity.php

@@ -267,12 +267,9 @@ class Activity
                 'activity_profile_id_verb_idx'             => ['profile_id', 'verb'],
                 'activity_replyto_idx'                     => ['reply_to'],
             ],
+            'fulltext indexes' => ['notice_fulltext_idx' => ['content']]
         ];
 
-        if (isset($_ENV['SOCIAL_DB_USE_FULLTEXT_SEARCH'])) {
-            $def['fulltext indexes'] = ['content' => ['content']];
-        }
-
         return $def;
     }
 }