feat: split Grafana dashboards into per-folder ConfigMaps

Replace monolithic dashboards-configmap.yaml with 10 dedicated files,
one per Grafana folder: Ingress, Observability, Infrastructure, Storage,
Identity, DevTools, Search, Media, La Suite, Communications.

New dashboards for Longhorn, PostgreSQL/CNPG, Cert-Manager, SeaweedFS,
Hydra, Kratos, Gitea, OpenSearch, LiveKit, La Suite golden signals
(Linkerd metrics), Matrix, and Email Pipeline.

base/monitoring/dashboards-search.yaml

@@ -0,0 +1,108 @@
+# Grafana dashboard ConfigMaps — Search
+---
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: grafana-dashboard-opensearch
+  namespace: monitoring
+  labels:
+    grafana_dashboard: "1"
+  annotations:
+    grafana_folder: "Search"
+data:
+  opensearch.json: |
+    {
+      "annotations": { "list": [] },
+      "editable": true,
+      "panels": [
+        {
+          "title": "Cluster Health",
+          "type": "stat",
+          "gridPos": { "h": 4, "w": 8, "x": 0, "y": 0 },
+          "datasource": { "uid": "prometheus" },
+          "targets": [
+            { "expr": "opensearch_cluster_health_status", "legendFormat": "health" }
+          ],
+          "fieldConfig": {
+            "defaults": { "mappings": [{"type":"value","options":{"0":{"text":"GREEN","color":"green"},"1":{"text":"YELLOW","color":"yellow"},"2":{"text":"RED","color":"red"}}}] }
+          }
+        },
+        {
+          "title": "Active Shards",
+          "type": "stat",
+          "gridPos": { "h": 4, "w": 8, "x": 8, "y": 0 },
+          "datasource": { "uid": "prometheus" },
+          "targets": [
+            { "expr": "opensearch_cluster_health_active_shards", "legendFormat": "shards" }
+          ]
+        },
+        {
+          "title": "Node Count",
+          "type": "stat",
+          "gridPos": { "h": 4, "w": 8, "x": 16, "y": 0 },
+          "datasource": { "uid": "prometheus" },
+          "targets": [
+            { "expr": "opensearch_cluster_health_number_of_nodes", "legendFormat": "nodes" }
+          ]
+        },
+        {
+          "title": "Index Size",
+          "type": "timeseries",
+          "gridPos": { "h": 8, "w": 12, "x": 0, "y": 4 },
+          "datasource": { "uid": "prometheus" },
+          "targets": [
+            {
+              "expr": "opensearch_index_store_size_bytes",
+              "legendFormat": "{{index}}"
+            }
+          ],
+          "fieldConfig": { "defaults": { "unit": "bytes" } }
+        },
+        {
+          "title": "JVM Heap Usage",
+          "type": "gauge",
+          "gridPos": { "h": 8, "w": 12, "x": 12, "y": 4 },
+          "datasource": { "uid": "prometheus" },
+          "targets": [
+            {
+              "expr": "opensearch_jvm_mem_heap_used_bytes / opensearch_jvm_mem_heap_max_bytes",
+              "legendFormat": "{{node}}"
+            }
+          ],
+          "fieldConfig": {
+            "defaults": { "unit": "percentunit", "max": 1, "thresholds": { "steps": [{"color":"green","value":null},{"color":"yellow","value":0.7},{"color":"red","value":0.85}] } }
+          }
+        },
+        {
+          "title": "Search Query Rate",
+          "type": "timeseries",
+          "gridPos": { "h": 8, "w": 12, "x": 0, "y": 12 },
+          "datasource": { "uid": "prometheus" },
+          "targets": [
+            {
+              "expr": "rate(opensearch_indices_search_query_total[5m])",
+              "legendFormat": "{{node}}"
+            }
+          ],
+          "fieldConfig": { "defaults": { "unit": "ops" } }
+        },
+        {
+          "title": "GC Collection Time",
+          "type": "timeseries",
+          "gridPos": { "h": 8, "w": 12, "x": 12, "y": 12 },
+          "datasource": { "uid": "prometheus" },
+          "targets": [
+            {
+              "expr": "rate(opensearch_jvm_gc_collection_time_seconds[5m])",
+              "legendFormat": "{{gc}}"
+            }
+          ],
+          "fieldConfig": { "defaults": { "unit": "s" } }
+        }
+      ],
+      "schemaVersion": 39,
+      "tags": ["opensearch", "search"],
+      "time": { "from": "now-1h", "to": "now" },
+      "title": "OpenSearch",
+      "uid": "opensearch"
+    }