Add observability stack with Grafana, Prometheus, Loki, and cAdvisor

- Introduced a new Grafana dashboard for monitoring Docker containers using cAdvisor.
- Created provisioning files for Grafana dashboards and data sources.
- Added Dockerfiles and configuration files for Loki and Prometheus.
- Implemented a Docker Compose stack for the observability services.
- Configured Traefik as a reverse proxy for the services with appropriate routing.
- Added scripts for SSH tunneling to access the telemetry dashboard.
- Included secrets management for Grafana admin credentials.

observability/grafana/provisioning/dashboards/default.yml

@@ -0,0 +1,27 @@
+apiVersion: 1
+
+# https://grafana.com/docs/grafana/latest/administration/provisioning/#dashboards
+providers:
+  # https://grafana.com/grafana/dashboards/19908-docker-container-monitoring-with-prometheus-and-cadvisor/
+  - name: cAdvisor
+    type: file
+    disableDeletion: true
+    allowUiUpdates: false
+    options:
+      path: /etc/grafana/provisioning/dashboards/19908_rev1.json
+
+  # https://grafana.com/grafana/dashboards/1860-node-exporter-full/
+  - name: Node Exporter
+    type: file
+    disableDeletion: true
+    allowUiUpdates: false
+    options:
+      path: /etc/grafana/provisioning/dashboards/1860_rev42.json
+
+  # https://grafana.com/grafana/dashboards/17346-traefik-official-standalone-dashboard/
+  - name: Traefik
+    type: file
+    disableDeletion: true
+    allowUiUpdates: false
+    options:
+      path: /etc/grafana/provisioning/dashboards/17346_rev9.json