Add new brand logo as favicon and navbar icon

- Set logo SRT.png as browser favicon
- Replace generic SVG icon with actual brand logo in navbar
- Logo now serves as the brand signature across the app

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

web/static/index.html

@@ -5,6 +5,9 @@
   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
   <title>RT Caption Generator</title>
 
+  <!-- Favicon -->
+  <link rel="icon" type="image/png" href="/static/logo SRT.png">
+
   <!-- Tailwind CSS (CDN) -->
   <script src="https://cdn.tailwindcss.com"></script>
   <script>
@@ -197,11 +200,7 @@
       <div class="flex items-center justify-between h-20">
         <!-- Logo / Brand -->
         <div class="flex items-center gap-3 animate-fade-in">
-          <div class="p-2 rounded-lg bg-gradient-to-br from-blue-500 to-purple-600 shadow-lg">
-            <svg class="w-6 h-6 text-white" fill="currentColor" viewBox="0 0 24 24">
-              <path d="M12 2C6.48 2 2 6.48 2 12s4.48 10 10 10 10-4.48 10-10S17.52 2 12 2zm0 18c-4.41 0-8-3.59-8-8s3.59-8 8-8 8 3.59 8 8-3.59 8-8 8zm3.5-9c.83 0 1.5-.67 1.5-1.5S16.33 8 15.5 8 14 8.67 14 9.5s.67 1.5 1.5 1.5zm-7 0c.83 0 1.5-.67 1.5-1.5S9.33 8 8.5 8 7 8.67 7 9.5 7.67 11 8.5 11zm3.5 6.5c2.33 0 4.31-1.46 5.11-3.5H6.89c.8 2.04 2.78 3.5 5.11 3.5z"/>
-            </svg>
-          </div>
+          <img src="/static/logo SRT.png" alt="RT Caption Generator" class="h-12 w-12 rounded-lg shadow-lg object-cover">
           <div>
             <h1 class="text-xl font-bold text-white hidden sm:block bg-gradient-to-r from-blue-400 to-purple-400 bg-clip-text text-transparent">
               Caption Generator