Switch from RabbitMQ to server-sent events

(not fully working yet)

backend/package.json

@@ -20,6 +20,7 @@
     "@types/node": "^14.14.9",
     "amqplib": "^0.6.0",
     "argon2": "^0.27.0",
+    "bi-directional-map": "^1.0.0",
     "body-parser": "^1.19.0",
     "chalk": "^4.1.0",
     "cors": "^2.8.5",
@@ -34,20 +35,20 @@
     "winston": "^3.3.3"
   },
   "devDependencies": {
+    "@types/amqplib": "0.5.14",
     "@types/argon2": "0.15.0",
     "@types/body-parser": "1.19.0",
     "@types/chalk": "2.2.0",
+    "@types/cors": "2.8.8",
     "@types/dotenv": "8.2.0",
     "@types/express": "4.17.8",
     "@types/figlet": "1.2.0",
+    "@types/jsonwebtoken": "8.5.0",
+    "@types/moment": "2.13.0",
     "@types/mongoose": "5.7.36",
     "@types/typescript": "2.0.0",
     "@types/winston": "2.4.4",
     "concurrently": "^5.3.0",
-    "nodemon": "^2.0.5",
-    "@types/jsonwebtoken": "8.5.0",
-    "@types/amqplib": "0.5.14",
-    "@types/cors": "2.8.8",
-    "@types/moment": "2.13.0"
+    "nodemon": "^2.0.5"
   }
 }