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

server/emails/components/Button.tsx

@@ -0,0 +1,24 @@
+import * as React from "react";
+
+type Props = {
+  href: string;
+  children: React.ReactNode;
+};
+
+export default (props: Props) => {
+  const style = {
+    display: "inline-block",
+    padding: "10px 20px",
+    color: "#FFFFFF",
+    background: "#000000",
+    borderRadius: "4px",
+    fontWeight: 500,
+    textDecoration: "none",
+    cursor: "pointer",
+  };
+  return (
+    <a {...props} style={style}>
+      {props.children}
+    </a>
+  );
+};