feat(horses-service): remove integration tests and obsolete configurations

- Deleted outdated integration test classes (`HorseServiceIntegrationTest`, `TransactionalContextTest`, and others) and test resources (`logback-test.xml`).
- Removed obsolete Gradle dependencies related to these tests and revised project module references.
- Simplified `DomPferd` domain model with minor refactorings for serialization and validation.

Signed-off-by: Stefan Mogeritsch <stefan.mo.co@gmail.com>

backend/services/persons/persons-service/src/main/kotlin/at/mocode/persons/service/config/DatabaseConfiguration.kt

@@ -3,8 +3,8 @@ package at.mocode.persons.service.config
 import at.mocode.persons.infrastructure.persistence.ZnsPersonTable
 import jakarta.annotation.PostConstruct
 import org.jetbrains.exposed.v1.jdbc.Database
-import org.jetbrains.exposed.v1.jdbc.SchemaUtils
 import org.jetbrains.exposed.v1.jdbc.transactions.transaction
+import org.jetbrains.exposed.v1.migration.jdbc.MigrationUtils
 import org.slf4j.LoggerFactory
 import org.springframework.beans.factory.annotation.Value
 import org.springframework.context.annotation.Configuration
@@ -24,7 +24,8 @@ class PersonsDatabaseConfiguration(
     log.info("Initialisiere Datenbank-Schema für Persons-Service...")
     Database.connect(jdbcUrl, user = username, password = password)
     transaction {
-      SchemaUtils.createMissingTablesAndColumns(ZnsPersonTable)
+      val statements = MigrationUtils.statementsRequiredForDatabaseMigration(ZnsPersonTable)
+      statements.forEach { exec(it) }
       log.info("Datenbank-Schema erfolgreich initialisiert")
     }
   }

backend/services/persons/persons-service/src/main/kotlin/at/mocode/persons/service/dev/ZnsPersonSeeder.kt

@@ -1,9 +1,9 @@
 package at.mocode.persons.service.dev
 
 import at.mocode.persons.infrastructure.persistence.ZnsPersonTable
-import org.jetbrains.exposed.v1.jdbc.SchemaUtils
 import org.jetbrains.exposed.v1.jdbc.batchInsert
 import org.jetbrains.exposed.v1.jdbc.transactions.transaction
+import org.jetbrains.exposed.v1.migration.jdbc.MigrationUtils
 import org.slf4j.LoggerFactory
 import org.springframework.beans.factory.annotation.Value
 import org.springframework.boot.CommandLineRunner
@@ -36,7 +36,8 @@ class ZnsPersonSeeder(
     }
     log.info("Starte ZNS-Personen-Import aus: {}", dir.absolutePath)
     transaction {
-      SchemaUtils.createMissingTablesAndColumns(ZnsPersonTable)
+      val statements = MigrationUtils.statementsRequiredForDatabaseMigration(ZnsPersonTable)
+      statements.forEach { exec(it) }
     }
     seedPersons(dir)
     log.info("ZNS-Personen-Import abgeschlossen.")