added cache, s3 to taskmanager, ask cache if result is the same, among others

backend/cache/src/lib.rs

@@ -1,6 +1,6 @@
 pub use fred::{
     clients::Pool,
-    interfaces::KeysInterface,
+    interfaces::{ClientLike, KeysInterface},
     prelude::*,
     types::{Expiration, SetOptions},
 };