Feat: Add Interfaces for unifying model method names

CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/datastructure/BoundedSpace.java

+package de.hft.stuttgart.citydoctor2.datastructure;
+
+import java.util.List;
+
+public interface BoundedSpace {
+
+    List<BoundarySurface> getBoundarySurfaces();
+
+    void addBoundarySurface(BoundarySurface boundarySurface);
+}

CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/datastructure/ConstructionObject.java

+package de.hft.stuttgart.citydoctor2.datastructure;
+
+import java.util.List;
+
+public interface ConstructionObject extends BoundedSpace{
+
+    List<? extends AbstractConstructiveElement> getConstructiveElements();
+
+    List<? extends Installation> getInstallations();
+
+    List<? extends AbstractFurniture> getFurniture();
+
+    List<? extends AbstractRoom>  getRooms();
+
+}

CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/datastructure/ConstructiveElement.java

+package de.hft.stuttgart.citydoctor2.datastructure;
+
+import java.util.List;
+
+public interface ConstructiveElement extends BoundedSpace{
+
+    List<AbstractConstructiveFillingElement> getFillings();
+
+}