[Glitch] Convert easy entrypoints files to Typescript

Port 36909065b5 to glitch-soc

Signed-off-by: Claire <claire.github-309c@sitedethib.com>

app/javascript/flavours/glitch/entrypoints/application.ts

@@ -0,0 +1,15 @@
+import '@/entrypoints/public-path';
+
+import { start } from 'flavours/glitch/common';
+import { loadLocale } from 'flavours/glitch/locales';
+import main from 'flavours/glitch/main';
+import { loadPolyfills } from 'flavours/glitch/polyfills';
+
+start();
+
+loadPolyfills()
+  .then(loadLocale)
+  .then(main)
+  .catch((e: unknown) => {
+    console.error(e);
+  });