fix: use host networking for voice services to eliminate docker-proxy overhead

Bridge mode created 600+ docker-proxy processes for LiveKit's UDP port-range
mappings (30000-30100, 50000-50200). Switch livekit-server, voice-agent, and
voice-service to network_mode: host for zero-overhead networking.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

deploy/docker/docker-compose.yml

@@ -312,17 +312,15 @@ services:
       - it0-network
 
   # ===== LiveKit Infrastructure =====
+  # NOTE: livekit-server, voice-agent, voice-service use host networking
+  # to eliminate docker-proxy overhead for real-time audio (WebRTC UDP).
+  # Bridge mode created 600+ docker-proxy processes for port-range mappings.
   livekit-server:
     image: livekit/livekit-server:latest
     container_name: it0-livekit-server
     restart: unless-stopped
+    network_mode: host
     command: --config /etc/livekit.yaml
-    ports:
-      - "17880:7880"
-      - "17881:7881"
-      - "3478:3478/udp"
-      - "30000-30100:30000-30100/udp"
-      - "50000-50200:50000-50200/udp"
     volumes:
       - ./livekit.yaml:/etc/livekit.yaml:ro
     healthcheck:
@@ -330,22 +328,21 @@ services:
       interval: 10s
       timeout: 5s
       retries: 3
-    networks:
-      - it0-network
 
   voice-agent:
     build:
       context: ../../packages/services/voice-agent
     container_name: it0-voice-agent
     restart: unless-stopped
+    network_mode: host
     volumes:
       - ../../data/voice-models/huggingface:/root/.cache/huggingface
       - ../../data/voice-models/torch-hub:/root/.cache/torch/hub
     environment:
-      - LIVEKIT_URL=ws://livekit-server:7880
+      - LIVEKIT_URL=ws://127.0.0.1:7880
       - LIVEKIT_API_KEY=devkey
       - LIVEKIT_API_SECRET=devsecret
-      - AGENT_SERVICE_URL=http://agent-service:3002
+      - AGENT_SERVICE_URL=http://127.0.0.1:13002
       - STT_PROVIDER=${STT_PROVIDER:-local}
       - TTS_PROVIDER=${TTS_PROVIDER:-local}
       - WHISPER_MODEL=${WHISPER_MODEL:-base}
@@ -362,24 +359,21 @@ services:
         condition: service_healthy
       agent-service:
         condition: service_healthy
-    networks:
-      - it0-network
 
-  # ===== Voice Service (legacy WebSocket + Twilio) =====
+  # ===== Voice Service (LiveKit token + Twilio) =====
   voice-service:
     build:
       context: ../../packages/services/voice-service
     container_name: it0-voice-service
     restart: unless-stopped
-    ports:
-      - "13008:3008"
+    network_mode: host
     volumes:
       - ../../data/voice-models/huggingface:/root/.cache/huggingface
       - ../../data/voice-models/torch-hub:/root/.cache/torch/hub
     environment:
       - ANTHROPIC_API_KEY=${ANTHROPIC_API_KEY}
       - ANTHROPIC_BASE_URL=${ANTHROPIC_BASE_URL}
-      - AGENT_SERVICE_URL=http://agent-service:3002
+      - AGENT_SERVICE_URL=http://127.0.0.1:13002
       - WHISPER_MODEL=${WHISPER_MODEL:-base}
       - KOKORO_MODEL=${KOKORO_MODEL:-kokoro-82m}
       - KOKORO_VOICE=${KOKORO_VOICE:-zf_xiaoxiao}
@@ -393,7 +387,7 @@ services:
       - OPENAI_TTS_VOICE=${OPENAI_TTS_VOICE:-coral}
       - LIVEKIT_API_KEY=devkey
       - LIVEKIT_API_SECRET=devsecret
-      - LIVEKIT_WS_URL=ws://154.84.135.121:17880
+      - LIVEKIT_WS_URL=ws://154.84.135.121:7880
     healthcheck:
       test: ["CMD-SHELL", "python3 -c \"import urllib.request; urllib.request.urlopen('http://localhost:3008/docs')\""]
       interval: 30s
@@ -402,8 +396,6 @@ services:
       start_period: 120s
     depends_on:
       - agent-service
-    networks:
-      - it0-network
 
   # ===== Frontend =====
   web-admin:

it0_app/lib/core/config/app_config.dart

@@ -16,14 +16,14 @@ class AppConfig {
   factory AppConfig.development() => const AppConfig(
     apiBaseUrl: 'http://10.0.2.2:18000',
     wsBaseUrl: 'ws://10.0.2.2:18000',
-    livekitUrl: 'ws://10.0.2.2:17880',
+    livekitUrl: 'ws://10.0.2.2:7880',
     environment: 'development',
   );
 
   factory AppConfig.production() => const AppConfig(
     apiBaseUrl: 'http://154.84.135.121:18000',
     wsBaseUrl: 'ws://154.84.135.121:18000',
-    livekitUrl: 'ws://154.84.135.121:17880',
+    livekitUrl: 'ws://154.84.135.121:7880',
     environment: 'production',
   );
 }