fix(K1): uppercase cluster-vars keys to match component substitution refs

Flux postBuild.substituteFrom is case-sensitive; platform/ components reference
${UPPERCASE} tokens but cluster-vars keys were lowercase -> none would resolve
(literal ${...} would reach the HelmReleases). Uppercased the ConfigMap data
keys + the dev/prod overlay patch paths. Every component ref now resolves;
clusters/dev & clusters/prod build; gate green. Clears the K1 landmine before
any platform un-suspend.

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>

clusters/dev/kustomization.yaml

@@ -54,33 +54,33 @@ patches:
       name: cluster-vars
     patch: |-
       - op: replace
-        path: /data/cluster_env
+        path: /data/CLUSTER_ENV
         value: "dev"
       # DNS-01 against LE staging while iterating (avoids prod rate limits) — ADR-0006.
       - op: replace
-        path: /data/acme_cluster_issuer
+        path: /data/ACME_CLUSTER_ISSUER
         value: "letsencrypt-staging"
       # dev mirrors prod's 3-node topology, so the replicated tier keeps 3 replicas.
       - op: replace
-        path: /data/longhorn_default_replica_count
+        path: /data/LONGHORN_DEFAULT_REPLICA_COUNT
         value: "3"
       # smaller retention / volumes to keep the dev workstation footprint light.
       - op: replace
-        path: /data/monitoring_prometheus_retention
+        path: /data/MONITORING_PROMETHEUS_RETENTION
         value: "3d"
       - op: replace
-        path: /data/monitoring_prometheus_pvc_size
+        path: /data/MONITORING_PROMETHEUS_PVC_SIZE
         value: "5Gi"
       - op: replace
-        path: /data/monitoring_loki_pvc_size
+        path: /data/MONITORING_LOKI_PVC_SIZE
         value: "5Gi"
       # single-replica control-plane addons in dev (no HA needed to iterate).
       - op: replace
-        path: /data/keycloak_replicas
+        path: /data/KEYCLOAK_REPLICAS
         value: "1"
       - op: replace
-        path: /data/oauth2_proxy_replicas
+        path: /data/OAUTH2_PROXY_REPLICAS
         value: "1"
       - op: replace
-        path: /data/velero_retention
+        path: /data/VELERO_RETENTION
         value: "72h"