fix(frigate): publish go2rtc WebRTC port 8555 (tcp+udp) on frigate-nvr

Camera cards using advanced-camera-card were stuck retrying WebRTC ICE
negotiation every few seconds (visible as dashboards "refreshing").
frigate-nvr had no published ports at all, so go2rtc's WebRTC listener
on 8555 was unreachable from browsers despite valid ICE candidates
already configured (VIP + CIDR + stun) in frigate/config.yml.

Publishing via ingress mode keeps this working regardless of which
swarm node Frigate lands on (no placement constraint on this service).

No Traefik/auth changes - HA<->Frigate signaling was already working
correctly over traefik_backend; only the browser<->go2rtc media path
was broken.

homeassistant/homeassistant.yaml

@@ -63,6 +63,15 @@ services:
       FRIGATE_RTSP_PASSWORD: "${FRIGATE_RTSP_PASSWORD}"
     networks:
       - traefik_backend
+    ports:
+      - target: 8555
+        published: 8555
+        protocol: udp
+        mode: ingress
+      - target: 8555
+        published: 8555
+        protocol: tcp
+        mode: ingress
     deploy:
       labels:
         - traefik.enable=true