chore: Move to Typescript (#2783)

This PR moves the entire project to Typescript. Due to the ~1000 ignores this will lead to a messy codebase for a while, but the churn is worth it – all of those ignore comments are places that were never type-safe previously.

closes #1282

app/components/LoadingIndicator/LoadingIndicator.ts

@@ -0,0 +1,16 @@
+import { observer } from "mobx-react";
+import * as React from "react";
+import useStores from "~/hooks/useStores";
+
+function LoadingIndicator() {
+  const { ui } = useStores();
+
+  React.useEffect(() => {
+    ui.enableProgressBar();
+    return () => ui.disableProgressBar();
+  }, [ui]);
+
+  return null;
+}
+
+export default observer(LoadingIndicator);