feat(clickhouse): wire Phase 4 stores with feature flags

Add conditional beans for ClickHouseDiagramStore, ClickHouseAgentEventRepository,
and ClickHouseLogStore. All default to ClickHouse (matchIfMissing=true).
PG/OS stores activate only when explicitly configured.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

cameleer3-server-app/src/main/resources/application.yml

@@ -52,6 +52,9 @@ cameleer:
     metrics: ${CAMELEER_STORAGE_METRICS:postgres}
     search: ${CAMELEER_STORAGE_SEARCH:opensearch}
     stats: ${CAMELEER_STORAGE_STATS:clickhouse}
+    diagrams: ${CAMELEER_STORAGE_DIAGRAMS:clickhouse}
+    events: ${CAMELEER_STORAGE_EVENTS:clickhouse}
+    logs: ${CAMELEER_STORAGE_LOGS:clickhouse}
 
 security:
   access-token-expiry-ms: 3600000