Address Copilot review comments and fix lint issues

- Import and use useMemo from React
- Memoize baseUrl to prevent unnecessary re-renders
- Memoize iframeOrigin for efficient message verification
- Use location.search from useLocation hook instead of window.location.search
- Update useEffect dependencies to use memoized values
- Fix code formatting with prettier

These changes improve performance by avoiding unnecessary computations
and follow React best practices for hooks.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

Author: MaxGhenis

src/applets/OBBBAHouseholdExplorer.jsx

@@ -2,7 +2,7 @@ import Header from "../layout/Header";
 import { Helmet } from "react-helmet";
 import style from "../style";
 import { useWindowHeight } from "../hooks/useWindow";
-import { useEffect, useRef } from "react";
+import { useEffect, useRef, useMemo } from "react";
 import { useNavigate, useLocation } from "react-router-dom";
 
 export default function OBBBAHouseholdExplorer() {
@@ -11,29 +11,43 @@ export default function OBBBAHouseholdExplorer() {
   const location = useLocation();
   const iframeRef = useRef(null);
 
-  // Get current URL parameters to forward to iframe
-  const urlParams = new URLSearchParams(window.location.search);
-  const baseUrl = process.env.REACT_APP_OBBBA_IFRAME_URL || "https://policyengine.github.io/obbba-scatter";
-  
+  // Memoize baseUrl to prevent unnecessary re-renders
+  const baseUrl = useMemo(
+    () =>
+      process.env.REACT_APP_OBBBA_IFRAME_URL ||
+      "https://policyengine.github.io/obbba-scatter",
+    [],
+  );
+
+  // Memoize iframe origin for efficient message verification
+  const iframeOrigin = useMemo(() => new URL(baseUrl).origin, [baseUrl]);
+
+  // Get current URL parameters to forward to iframe using location hook
+  const urlParams = new URLSearchParams(location.search);
+
   // Construct iframe URL with forwarded parameters
-  const iframeUrl = urlParams.toString() ? `${baseUrl}?${urlParams.toString()}` : baseUrl;
+  const iframeUrl = urlParams.toString()
+    ? `${baseUrl}?${urlParams.toString()}`
+    : baseUrl;
 
   useEffect(() => {
     // Listen for messages from the iframe
     const handleMessage = (event) => {
       // Verify the message is from our iframe
-      if (event.origin !== new URL(baseUrl).origin) return;
-      
+      if (event.origin !== iframeOrigin) return;
+
       // Handle URL update messages from the iframe
-      if (event.data?.type === 'urlUpdate' && event.data?.params) {
+      if (event.data?.type === "urlUpdate" && event.data?.params) {
         const newParams = new URLSearchParams(event.data.params);
-        navigate(`${location.pathname}?${newParams.toString()}`, { replace: true });
+        navigate(`${location.pathname}?${newParams.toString()}`, {
+          replace: true,
+        });
       }
     };
 
-    window.addEventListener('message', handleMessage);
-    return () => window.removeEventListener('message', handleMessage);
-  }, [navigate, location.pathname, baseUrl]);
+    window.addEventListener("message", handleMessage);
+    return () => window.removeEventListener("message", handleMessage);
+  }, [navigate, location.pathname, iframeOrigin]);
 
   return (
     <>