selkies: enable internal TURN relay (LAN) so WebRTC media works behind nginx

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

services/selkies.nix

@@ -67,6 +67,8 @@ in
             -e NVIDIA_DRIVER_CAPABILITIES=all \
             --shm-size=2g \
             -p 127.0.0.1:8093:8080 \
+            -p 3478:3478 -p 3478:3478/udp \
+            -p 65532-65535:65532-65535/udp \
             -e TZ=Europe/Stockholm \
             -e DISPLAY_SIZEW=1280 -e DISPLAY_SIZEH=720 \
             -e DISPLAY_REFRESH=30 -e DISPLAY_DPI=96 -e DISPLAY_CDEPTH=24 \
@@ -75,6 +77,10 @@ in
             -e SELKIES_VIDEO_BITRATE=8000 \
             -e SELKIES_FRAMERATE=30 \
             -e SELKIES_ENABLE_BASIC_AUTH=false \
+            -e SELKIES_TURN_HOST=10.0.0.1 \
+            -e SELKIES_TURN_PROTOCOL=udp \
+            -e SELKIES_TURN_PORT=3478 \
+            -e TURN_MIN_PORT=65532 -e TURN_MAX_PORT=65535 \
             -v /var/lib/selkies/home:/home/ubuntu \
             selkies-gw:local
         '';