Enable dark mode logging

The default colors in the debug output of vue-socket.io are tuned for light mode consoles, and viewing them in dark mode is effectively impossible. Since the base version does not yet support switching the output color, we instead switch to PhantasWeng's patched version, pending MetinSeylan/Vue-Socket.io#231.

Author: thislooksfun

frontend/package-lock.json

@@ -12,7 +12,7 @@
     "core-js": "^3.4.4",
     "v-click-outside": "^3.0.0",
     "vue": "^2.6.10",
-    "vue-socket.io": "^3.0.7"
+    "vue-socket.io": "git+https://github.com/PhantasWeng/Vue-Socket.io.git#cef2ca40992500b7ae5dd3917268167446cc509c"
   },
   "devDependencies": {
     "@vue/cli-plugin-babel": "^4.1.0",

frontend/package.json

@@ -9,6 +9,7 @@ Vue.use(vClickOutside);
 Vue.use(
   new VueSocketIO({
     debug: true,
+    darkMode: true,
     connection: io(), // eslint-disable-line no-undef
   })
 );