ui: use sharedworker for messages conn

packages/ui-default/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@hydrooj/ui-default",
-  "version": "4.30.11",
+  "version": "4.31.0",
   "author": "undefined <i@undefined.moe>",
   "license": "AGPL-3.0",
   "main": "hydro.js",
@@ -18,6 +18,7 @@
     "@types/katex": "^0.11.1",
     "@types/qrcode": "^1.4.2",
     "@types/redux-logger": "^3.0.9",
+    "@types/sharedworker": "^0.0.64",
     "@types/sockjs-client": "^1.5.1",
     "@undefined-moe/monaco-yaml": "^2.5.1",
     "ansi_up": "^5.1.0",
@@ -74,6 +75,7 @@
     "react-dom": "^17.0.2",
     "react-redux": "^7.2.6",
     "react-split-pane": "^0.1.92",
+    "reconnecting-websocket": "^4.4.0",
     "redux": "^4.1.2",
     "redux-logger": "^3.0.6",
     "redux-promise-middleware": "^6.1.2",