OZG-5776 xta-adapter: Split xdomea and fim handlers

...c/main/java/de/ozgcloud/eingang/fim/FimMessageMapper.java

...in/java/de/ozgcloud/eingang/fim/FimXtaMessageHandler.java

...a/de/ozgcloud/eingang/xdomea/XdomeaXtaMessageHandler.java

...ain/java/de/ozgcloud/eingang/xdomea/XtaMessageMapper.java

...c/main/java/de/ozgcloud/eingang/xta/FimMessageMapper.java

.../main/java/de/ozgcloud/eingang/xta/XtaMessageHandler.java

...main/java/de/ozgcloud/eingang/xta/XtaMessageMetaData.java

...ter/src/main/java/de/ozgcloud/eingang/xta/XtaService.java

.../ozgcloud/eingang/xdomea/XdomeaXtaMessageHandlerTest.java

...java/de/ozgcloud/eingang/xdomea/XtaMessageMapperTest.java

...t/java/de/ozgcloud/eingang/xta/FormHeaderTestFactory.java

...pter/src/test/java/de/ozgcloud/eingang/xta/XtaITCase.java

...e/ozgcloud/eingang/xta/XtaMessageMetaDataTestFactory.java

...src/test/java/de/ozgcloud/eingang/xta/XtaServiceTest.java