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

src/database/models/mod.rs

@@ -48,4 +48,6 @@ pub enum DatabaseError {
     SerdeCacheError(#[from] serde_json::Error),
     #[error("Schema error: {0}")]
     SchemaError(String),
+    #[error("Timeout when waiting for cache subscriber")]
+    CacheTimeout,
 }