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/hooks/useIdle.ts

@@ -0,0 +1,52 @@
+import * as React from "react";
+
+const activityEvents = [
+  "click",
+  "mousemove",
+  "keydown",
+  "DOMMouseScroll",
+  "mousewheel",
+  "mousedown",
+  "touchstart",
+  "touchmove",
+  "focus",
+];
+
+/**
+ * Hook to detect user idle state.
+ *
+ * @param {number} timeToIdle
+ * @returns boolean if the user is idle
+ */
+export default function useIdle(timeToIdle: number = 3 * 60 * 1000) {
+  const [isIdle, setIsIdle] = React.useState(false);
+  const timeout = React.useRef<ReturnType<typeof setTimeout>>();
+
+  const onActivity = React.useCallback(() => {
+    if (timeout.current) {
+      clearTimeout(timeout.current);
+    }
+
+    timeout.current = setTimeout(() => {
+      setIsIdle(true);
+    }, timeToIdle);
+  }, [timeToIdle]);
+
+  React.useEffect(() => {
+    const handleUserActivityEvent = () => {
+      setIsIdle(false);
+      onActivity();
+    };
+
+    activityEvents.forEach((eventName) =>
+      window.addEventListener(eventName, handleUserActivityEvent)
+    );
+    return () => {
+      activityEvents.forEach((eventName) =>
+        window.removeEventListener(eventName, handleUserActivityEvent)
+      );
+    };
+  }, [onActivity]);
+
+  return isIdle;
+}