Filter Promtail to only collect weatherust project logs

Add Docker SD filter to only scrape containers from weatherust
compose project. This prevents Promtail from collecting logs from
ALL containers on the host (immich, traefik, portainer, etc.).

Problem: With 20+ containers, Grafana was trying to process too
many log streams, causing React to block the UI thread with
violations like 'message handler took 243ms'.

Solution: Filter at the source - only collect weatherust logs.
This dramatically reduces the number of streams Grafana needs
to process, fixing the browser freezing issue.

Author: jsprague84

promtail-config.yml

@@ -9,11 +9,14 @@ clients:
   - url: http://loki:3100/loki/api/v1/push
 
 scrape_configs:
-  # Scrape all Docker container logs
+  # Scrape only weatherust project Docker container logs
   - job_name: docker
     docker_sd_configs:
       - host: unix:///var/run/docker.sock
         refresh_interval: 5s
+        filters:
+          - name: label
+            values: ["com.docker.compose.project=weatherust"]
     relabel_configs:
       # Use container name as job label
       - source_labels: ['__meta_docker_container_name']