feat: auto-logout after 1 hour of inactivity

Tracks user activity events (mouse, keyboard, scroll, touch) and resets
a 60-minute idle timer on each event. Shows a warning toast at 55 minutes,
then calls logoutMutation at 60 minutes to clear the session.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/Frontend/src/hooks/use-auth.tsx

@@ -1,4 +1,4 @@
-import { createContext, ReactNode, useContext } from "react";
+import { createContext, ReactNode, useContext, useEffect, useRef } from "react";
 import {
   useQuery,
   useMutation,
@@ -131,6 +131,51 @@ export function AuthProvider({ children }: { children: ReactNode }) {
     },
   });
 
+  const IDLE_TIMEOUT = 60 * 60 * 1000;
+  const WARN_BEFORE = 5 * 60 * 1000;
+
+  const logoutTimer = useRef<ReturnType<typeof setTimeout> | null>(null);
+  const warnTimer = useRef<ReturnType<typeof setTimeout> | null>(null);
+  const warnedRef = useRef(false);
+
+  useEffect(() => {
+    if (!user) return;
+
+    const clearTimers = () => {
+      if (logoutTimer.current) clearTimeout(logoutTimer.current);
+      if (warnTimer.current) clearTimeout(warnTimer.current);
+    };
+
+    const resetTimers = () => {
+      clearTimers();
+      warnedRef.current = false;
+
+      warnTimer.current = setTimeout(() => {
+        if (!warnedRef.current) {
+          warnedRef.current = true;
+          toast({
+            title: "Session expiring soon",
+            description: "You will be logged out in 5 minutes due to inactivity.",
+            duration: 10000,
+          });
+        }
+      }, IDLE_TIMEOUT - WARN_BEFORE);
+
+      logoutTimer.current = setTimeout(() => {
+        logoutMutation.mutate();
+      }, IDLE_TIMEOUT);
+    };
+
+    const events = ["mousemove", "mousedown", "keydown", "scroll", "touchstart", "click"];
+    events.forEach((e) => window.addEventListener(e, resetTimers, { passive: true }));
+    resetTimers();
+
+    return () => {
+      clearTimers();
+      events.forEach((e) => window.removeEventListener(e, resetTimers));
+    };
+  }, [user]);
+
   return (
     <AuthContext.Provider
       value={{