Fix cache stampede issues + generalize cache (#884)

* caching changes

* fix cache stampede issues

* Use pub/sub for better DB fetches

* remove pubsub

* remove debugs

* Fix caches not working

* fix search indexing removal

.sqlx/query-f62ec19e7e23ec98ad38f79ba28066f1b13a607923003699378bda895aab3a84.json

@@ -0,0 +1,59 @@
+{
+  "db_name": "PostgreSQL",
+  "query": "\n                    SELECT DISTINCT mod_id, mg.image_url, mg.featured, mg.name, mg.description, mg.created, mg.ordering\n                    FROM mods_gallery mg\n                    INNER JOIN mods m ON mg.mod_id = m.id\n                    WHERE m.id = ANY($1) OR m.slug = ANY($2)\n                    ",
+  "describe": {
+    "columns": [
+      {
+        "ordinal": 0,
+        "name": "mod_id",
+        "type_info": "Int8"
+      },
+      {
+        "ordinal": 1,
+        "name": "image_url",
+        "type_info": "Varchar"
+      },
+      {
+        "ordinal": 2,
+        "name": "featured",
+        "type_info": "Bool"
+      },
+      {
+        "ordinal": 3,
+        "name": "name",
+        "type_info": "Varchar"
+      },
+      {
+        "ordinal": 4,
+        "name": "description",
+        "type_info": "Varchar"
+      },
+      {
+        "ordinal": 5,
+        "name": "created",
+        "type_info": "Timestamptz"
+      },
+      {
+        "ordinal": 6,
+        "name": "ordering",
+        "type_info": "Int8"
+      }
+    ],
+    "parameters": {
+      "Left": [
+        "Int8Array",
+        "TextArray"
+      ]
+    },
+    "nullable": [
+      false,
+      false,
+      true,
+      true,
+      true,
+      false,
+      false
+    ]
+  },
+  "hash": "f62ec19e7e23ec98ad38f79ba28066f1b13a607923003699378bda895aab3a84"
+}