fix: resolve Hibernate schema validation and transaction propagation issues

  - Use @JdbcTypeCode(SqlTypes.ARRAY) for PostgreSQL array types
  - Implement REQUIRES_NEW transaction for error handling
  - Fix unit test mock environment compatibility

  Fixes #40 (partial), addresses core testing infrastructure

Author: lmj

connectors/src/test/java/com/dbsyncer/connectors/storage/JdbcOffsetBackingStoreIntegrationTest.java

@@ -24,7 +24,7 @@
 /**
  * Integration test for JdbcOffsetBackingStore using Testcontainers.
  */
-@Testcontainers
+@Testcontainers(disabledWithoutDocker = true)
 class JdbcOffsetBackingStoreIntegrationTest {
 
     @Container