feat(alloy): add journal relabeling and kottos integration on puck

Introduce structured journal relabel rules on puck to tag Pallas-managed
units with {service, project, component} labels matching the Mnemosyne
and Daedalus schema. Add kottos release variable and vault secrets
example entries for the new Pallas FastAgent runtime.

Remove the defunct mnemosyne syslog listener now that Mnemosyne ships
JSON logs via the docker-socket pipeline.

ansible/pplg/dashboards_provider.yml.j2

@@ -0,0 +1,23 @@
+# Grafana dashboard file provider
+# Deployed to: /etc/grafana/provisioning/dashboards/puck.yaml
+#
+# Grafana polls the ``path`` every ``updateIntervalSeconds`` and re-imports
+# any JSON file it finds.  Each dashboard JSON lives in that directory and
+# is owned by Ansible — operators should not edit dashboards through the
+# Grafana UI (changes won't survive a deploy; export the final JSON and
+# land it in this role).
+apiVersion: 1
+
+providers:
+  - name: 'puck'
+    orgId: 1
+    folder: 'Puck Services'
+    folderUid: puck-services
+    type: file
+    disableDeletion: false
+    editable: true
+    allowUiUpdates: false
+    updateIntervalSeconds: 30
+    options:
+      path: /var/lib/grafana/dashboards
+      foldersFromFilesStructure: false