[Glitch] Add polling and automatic redirection to /start on email confirmation

Port e60414792d to glitch-soc

app/javascript/core/theme.yml

@@ -16,4 +16,5 @@ pack:
   modal: public.js
   public: public.js
   settings: settings.js
+  sign_up:
   share:

app/javascript/flavours/glitch/packs/sign_up.js

@@ -0,0 +1,15 @@
+import 'packs/public-path';
+import ready from 'flavours/glitch/ready';
+import axios from 'axios';
+
+ready(() => {
+  setInterval(() => {
+    axios.get('/api/v1/emails/check_confirmation').then((response) => {
+      if (response.data) {
+        window.location = '/start';
+      }
+    }).catch(error => {
+      console.error(error);
+    });
+  }, 5000);
+});

app/javascript/flavours/glitch/theme.yml

@@ -20,6 +20,7 @@ pack:
   modal:
   public: packs/public.jsx
   settings: packs/settings.js
+  sign_up: packs/sign_up.js
   share: packs/share.jsx
 
 #  (OPTIONAL) The directory which contains localization files for

app/javascript/flavours/vanilla/theme.yml

@@ -20,6 +20,7 @@ pack:
   modal:
   public: public.jsx
   settings: public.jsx
+  sign_up: sign_up.js
   share: share.jsx
 
 #  (OPTIONAL) The directory which contains localization files for