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

shared/utils/unescape.ts

@@ -0,0 +1,7 @@
+const unescape = (text: string) => {
+  return text
+    .replace(/\\([\\`*{}[\]()#+\-.!_>])/g, "$1")
+    .replace(/\n\\\n/g, "\n\n");
+};
+
+export default unescape;