feat: architect observability stack with Garage S3 backend

[ProjectInitiative]

Architect and deploy observability stack (Prometheus, Thanos, Loki) on Capstan cluster, backed by Garage S3 on Management Cluster, with RAM optimization for S3 write batching.

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PR created automatically by Jules for task 11620278594626914662 started by @ProjectInitiative

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[github-actions]

Manifest Changes Detected

Click to expand diff

Only in manifests-pr/1-manifest: argoproj.io_v1alpha1-application-argocd-cc-observability.yaml
diff -r -u manifests-main/1-manifest/argoproj.io_v1alpha1-application-argocd-mc-garage.yaml manifests-pr/1-manifest/argoproj.io_v1alpha1-application-argocd-mc-garage.yaml
--- manifests-main/1-manifest/argoproj.io_v1alpha1-application-argocd-mc-garage.yaml	2026-02-27 03:53:29.806693751 +0000
+++ manifests-pr/1-manifest/argoproj.io_v1alpha1-application-argocd-mc-garage.yaml	2026-02-27 03:53:44.310783410 +0000
@@ -42,6 +42,20 @@
           extraVolumeMounts:
             - name: snapshots
               mountPath: /snapshots
+          ingress:
+            s3:
+              api:
+                enabled: true
+                ingressClassName: tailscale
+                hosts:
+                  - host: s3.moonwake.io
+                    paths:
+                      - path: /
+                        pathType: Prefix
+                tls:
+                  - secretName: garage-ingress-cert
+                    hosts:
+                      - s3.moonwake.io
       - name: KUSTOMIZE_PATCH
         value: |
           - op: add
@@ -76,7 +90,7 @@
               serviceAccount: operator-auth-sa
             method: kubernetes
             mount: kubernetes_cluster_mc
-            namespace: production
+            namespace: monitoring
         target:
           kind: VaultAuth
           name: placeholder-auth
@@ -104,7 +118,7 @@
               create: true
               name: garage-rpc-secret
             mount: k8s
-            namespace: production
+            namespace: monitoring
             path: garage/rpc
             type: kv-v2
             vaultAuthRef: operator-auth
diff -r -u manifests-main/1-manifest/argoproj.io_v1alpha1-application-argocd-mc-postgres-cluster.yaml manifests-pr/1-manifest/argoproj.io_v1alpha1-application-argocd-mc-postgres-cluster.yaml
--- manifests-main/1-manifest/argoproj.io_v1alpha1-application-argocd-mc-postgres-cluster.yaml	2026-02-27 03:53:29.806562578 +0000
+++ manifests-pr/1-manifest/argoproj.io_v1alpha1-application-argocd-mc-postgres-cluster.yaml	2026-02-27 03:53:44.311123230 +0000
@@ -32,7 +32,7 @@
               serviceAccount: operator-auth-sa
             method: kubernetes
             mount: kubernetes_cluster_mc
-            namespace: production
+            namespace: monitoring
         target:
           kind: VaultAuth
           name: placeholder-auth
@@ -60,7 +60,7 @@
               create: true
               name: postgres-cluster-s3
             mount: k8s
-            namespace: production
+            namespace: monitoring
             path: cnpg/s3
             type: kv-v2
             vaultAuthRef: operator-auth