feat(voice): add WebRTC voice channels with Cloudflare TURN support

Add voice channel functionality with WebRTC peer-to-peer audio:
- Add VoiceSignalingConsumer for WebRTC signaling and peer coordination
- Add GlobalConsumer for real-time presence and voice status updates
- Add voice channel type to Channel model with current_voice_channel tracking on UserProfile
- Add voice controls UI (mute, deafen, disconnect) in status panel
- Add voice member list display in sidebar with avatar support
- Add

chat/views.py

@@ -221,3 +221,42 @@ def handler404(request, exception):
 
 def handler500(request):
     return render(request, 'chat/500.html', status=500)
+
+
+import urllib.request
+import urllib.error
+import json
+from django.conf import settings
+
+@login_required
+def voice_credentials_view(request):
+    account_id = getattr(settings, 'CLOUDFLARE_ACCOUNT_ID', '')
+    api_token = getattr(settings, 'CLOUDFLARE_API_TOKEN', '')
+    turn_key_id = getattr(settings, 'CLOUDFLARE_TURN_KEY_ID', '')
+
+    if not all([account_id, api_token, turn_key_id]):
+        return JsonResponse({
+            "iceServers": [
+                {"urls": ["stun:stun.cloudflare.com:3478", "stun:stun.cloudflare.com:53"]}
+            ]
+        })
+
+    url = f"https://rtc.live.cloudflare.com/v1/turn/keys/{turn_key_id}/credentials/generate-ice-servers"
+    headers = {
+        "Authorization": f"Bearer {api_token}",
+        "Content-Type": "application/json"
+    }
+    body = json.dumps({"ttl": 86400}).encode("utf-8")
+
+    req = urllib.request.Request(url, data=body, headers=headers, method="POST")
+    try:
+        with urllib.request.urlopen(req, timeout=5) as response:
+            res_data = json.loads(response.read().decode())
+            return JsonResponse(res_data)
+    except urllib.error.URLError as e:
+        return JsonResponse({
+            "error": str(e),
+            "iceServers": [
+                {"urls": ["stun:stun.cloudflare.com:3478", "stun:stun.cloudflare.com:53"]}
+            ]
+        })