feat: add Ntfy notification service

nodes/heimdall/ntfy/compose.yaml

@@ -0,0 +1,24 @@
+name: ntfy
+services:
+  ntfy:
+    image: binwiederhier/ntfy:latest
+    container_name: ntfy
+    restart: unless-stopped
+    command:
+      - serve
+    volumes:
+      - /mnt/appdata/ntfy/data:/var/lib/ntfy
+    networks:
+      - proxy-net
+    labels:
+      - "traefik.enable=true"
+      - "traefik.http.routers.ntfy.rule=Host(`ntfy.castaldifamily.com`)"
+      - "traefik.http.routers.ntfy.entrypoints=websecure"
+      - "traefik.http.routers.ntfy.tls=true"
+      - "traefik.http.routers.ntfy.tls.certresolver=cloudflare"
+      - "traefik.http.routers.ntfy.middlewares=authentik-auth@file"
+      - "traefik.http.services.ntfy.loadbalancer.server.port=80"
+
+networks:
+  proxy-net:
+    external: true