[EC-272] Web workers using EncryptionService (#3532)

* Add item decryption to encryptService
* Create multithreadEncryptService subclass to handle web workers
* Create encryption web worker
* Refactor cipherService to use new interface
* Update dependencies

apps/desktop/config/base.json

@@ -1,4 +1,6 @@
 {
   "dev_flags": {},
-  "flags": {}
+  "flags": {
+    "multithreadDecryption": false
+  }
 }