Add request queue status indicator to UI

- Added visual queue status display showing pending and active requests
- Updates in real-time (every 500ms) to show current queue state
- Only visible when there are requests in queue or being processed
- Helps users understand system load and request processing

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

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

templates/index.html

@@ -184,6 +184,13 @@
                 <i class="fas fa-microphone"></i>
             </button>
             <p class="status-indicator" id="statusIndicator">Click to start recording</p>
+            <!-- Queue Status Indicator -->
+            <div id="queueStatus" class="text-center mt-2" style="display: none;">
+                <small class="text-muted">
+                    <i class="fas fa-list"></i> Queue: <span id="queueLength">0</span> | 
+                    <i class="fas fa-sync"></i> Active: <span id="activeRequests">0</span>
+                </small>
+            </div>
         </div>
 
         <div class="text-center mt-3">