Fix frigate-notify: webapi polling, dedup, hi-res snapshots (#242)

## Summary
- Switch from MQTT to webapi polling (v0.5.4 requires only one method)
- Poll every 15s for responsive alerts
- **`notify_once: true`** — one notification per event instead of repeats as object changes zones
- **`nosnap: drop`** — skip events without snapshots (was causing all events to be dropped on v0.3.5)
- **`snap_hires: true`** — use recording stream for higher quality snapshot images

## Deployment and Testing
- [ ] Sync: `argocd app set frigate --revision fix/frigate-notify-config && argocd app sync frigate`
- [ ] Verify pod starts: `kubectl --context=k3s-ringtail -n frigate get pods -l app=frigate-notify`
- [ ] Check logs for successful startup and event processing (no "No snapshot" drops)
- [ ] Wait for a motion event and confirm single ntfy notification with hi-res snapshot
- [ ] After merge: `argocd app set frigate --revision main && argocd app sync frigate`

Reviewed-on: https://forge.ops.eblu.me/eblume/blumeops/pulls/242

argocd/manifests/frigate/configmap-notify.yaml

@@ -11,17 +11,17 @@ data:
 
       webapi:
         enabled: true
+        interval: 15
 
       mqtt:
-        enabled: true
-        server: mosquitto.mqtt.svc.cluster.local
-        port: 1883
-        clientid: frigate-notify
-        topic_prefix: frigate
+        enabled: false
 
     alerts:
       general:
         title: "Frigate Alert"
+        nosnap: drop
+        snap_hires: true
+        notify_once: true
 
       zones:
         unzoned: drop

docs/changelog.d/fix-frigate-notify-config.bugfix.md

@@ -0,0 +1 @@
+Fix frigate-notify notification pipeline: switch to webapi polling, enable dedup, drop events without snapshots, use hi-res snapshots