feat(ssr): add Google Analytics tracking to index.html

- Integrated Google Tag Manager for enhanced tracking and analytics capabilities.
- Added asynchronous loading of gtag.js and configuration for tracking ID G-DZMBZBW3EC.

Signed-off-by: Innei <tukon479@gmail.com>

Author: Innei

apps/ssr/index.html

@@ -19,7 +19,17 @@
 
     <meta name="apple-itunes-app" content="app-id=6739802604" />
     <link rel="manifest" href="/manifest.json" />
+    <!-- Google tag (gtag.js) -->
+    <script async src="https://www.googletagmanager.com/gtag/js?id=G-DZMBZBW3EC"></script>
+    <script>
+      window.dataLayer = window.dataLayer || []
+      function gtag() {
+        dataLayer.push(arguments)
+      }
+      gtag("js", new Date())
 
+      gtag("config", "G-DZMBZBW3EC")
+    </script>
     <script>
       function setTheme() {
         let e = "follow:color-mode",