fix: add Kafka topics configuration to metadata Helm values

- Add kafka.topics section to values.yaml with partitions, replicas, retention, and segment settings
- Add kafka schema definition to values.schema.json for Helm validation
- Fixes Helm template error: nil pointer evaluating interface {}.topics

Author: batazor

boundaries/metadata/ops/metadata/values.schema.json

@@ -219,6 +219,38 @@
       },
       "type": "object"
     },
+    "kafka": {
+      "properties": {
+        "topics": {
+          "properties": {
+            "partitions": {
+              "type": "integer"
+            },
+            "replicas": {
+              "type": "integer"
+            },
+            "retention": {
+              "properties": {
+                "ms": {
+                  "type": "integer"
+                }
+              },
+              "type": "object"
+            },
+            "segment": {
+              "properties": {
+                "bytes": {
+                  "type": "integer"
+                }
+              },
+              "type": "object"
+            }
+          },
+          "type": "object"
+        }
+      },
+      "type": "object"
+    },
     "monitoring": {
       "properties": {
         "enabled": {

boundaries/metadata/ops/metadata/values.yaml

@@ -132,6 +132,17 @@ service:
       protocol: TCP
       public: true
 
+# ==============================================================================
+# Kafka topics configuration
+kafka:
+  topics:
+    partitions: 1
+    replicas: 3 # Minimum replicas for production Kafka cluster
+    retention:
+      ms: 7200000 # 2 hours
+    segment:
+      bytes: 31457280 # 30MB
+
 # ==============================================================================
 # Prometheus Operator ServiceMonitor configuration
 monitoring: