fix(search): prevent SSR errors by checking window existence

Add checks for window existence before accessing localStorage to avoid server-side rendering errors. Also remove redundant SearchIntegration instantiation and improve type safety in event target handling.

Author: leonism

src/components/search/SearchOverlay.astro

@@ -1,7 +1,8 @@
 ---
 import { getLangFromUrl } from "@/i18n/utils";
 import type { LanguageKey } from "@/i18n/types";
-import type { SearchResult } from '../../features/search/EnterpriseSearchEngine.js';
+import EnterpriseSearchEngine, { type SearchResult } from '../../features/search/EnterpriseSearchEngine';
+import { searchIntegration } from '../../features/search/searchIntegration';
 ---
 
 <section
@@ -67,7 +68,8 @@ import type { SearchResult } from '../../features/search/EnterpriseSearchEngine.
     }
 
     const searchEngine = new EnterpriseSearchEngine();
-    const searchIntegration = new SearchIntegration(); // Although not directly used here, it's good to have it initialized if needed elsewhere.
+    // Use the already exported instance of searchIntegration
+    // const searchIntegration = new SearchIntegration(); 
 
     let allDocuments = [];
 
@@ -161,7 +163,7 @@ import type { SearchResult } from '../../features/search/EnterpriseSearchEngine.
     // Close overlay when clicking outside the content area
     searchOverlay.addEventListener("click", (event) => {
       const contentArea = searchOverlay.querySelector(".w-full.max-w-3xl");
-      if (contentArea && !contentArea.contains(event.target as Node)) {
+      if (contentArea && !contentArea.contains(event.target)) {
         toggleSearchOverlay(false);
       }
     });

src/features/search/EnterpriseSearchEngine.ts

@@ -100,7 +100,9 @@ class EnterpriseSearchEngine {
   ]);
 
   constructor() {
-    this.loadAnalyticsFromStorage();
+    if (typeof window !== 'undefined') {
+      this.loadAnalyticsFromStorage();
+    }
   }
 
   /**
@@ -634,6 +636,7 @@ class EnterpriseSearchEngine {
   }
 
   private loadAnalyticsFromStorage(): void {
+    if (typeof window === 'undefined') return;
     try {
       const stored = localStorage.getItem("search-analytics");
       if (stored) {
@@ -650,6 +653,7 @@ class EnterpriseSearchEngine {
   }
 
   private saveAnalyticsToStorage(): void {
+    if (typeof window === 'undefined') return;
     try {
       localStorage.setItem("search-analytics", JSON.stringify(this.analytics));
     } catch (error) {