feat: Add 10 new stacks (Batch 1)

Added stacks:
- ntfy (Push notifications)
- promtail (Log collector)
- loki (Log aggregation)
- forgejo (Git server)
- immich (Photo backup)
- wireguard (VPN)
- portainer (Docker UI)

All stacks include:
- compose.yml with proper configuration
- README.md with deployment info
- stack.toml for Komodo Resource Sync

stacks/promtail/compose.yml

@@ -0,0 +1,19 @@
+services:
+  promtail:
+    image: grafana/promtail:latest
+    container_name: promtail
+    restart: unless-stopped
+    volumes:
+      - /var/log:/var/log:ro
+      - /var/lib/docker/containers:/var/lib/docker/containers:ro
+      - promtail_data:/tmp
+    command: -config.file=/etc/promtail/config.yml
+    networks:
+      - monitoring
+
+volumes:
+  promtail_data:
+
+networks:
+  monitoring:
+    driver: bridge